220-1101 Practice Exam 51 — 20 Questions

Question 1

A user reports that their workstation experiences intermittent network disconnections, often during peak office hours. The technician tests the Cat6 Ethernet cable with a continuity tester; the cable passes all four pairs. The network adapter is set to auto-negotiate and reports a link speed of 1 Gbps when connected. However, after observing the switch port, the technician notices a high number of CRC errors and late collisions. The cable runs through a dropped ceiling and is routed near fluorescent light ballasts. Which of the following should the technician do FIRST to resolve the issue?

Accepted Answer

Replace the network cable with a shielded (STP) cable. The high CRC errors and late collisions are classic symptoms of electromagnetic interference (EMI) corrupting the signal, which is consistent with the cable being routed near fluorescent light ballasts. Since the Cat6 cable passes continuity but the errors persist, the issue is noise, not a broken wire. Replacing the unshielded twisted pair (UTP) cable with a shielded (STP) cable will protect the signal from EMI, directly addressing the root cause.

Answer

Configure jumbo frames on the workstation and switch

Answer

Replace the network interface card (NIC) in the workstation

Answer

Replace the switch with one that supports auto-MDI/X

Question 2

A user's Android smartphone recently got a swollen battery and feels warm to the touch even when not in use. The technician checks the battery health using the built-in diagnostic tool, which reports 'Good'. The user mentions the phone was dropped onto a hardwood floor a few days ago. Which of the following is the MOST likely cause?

Accepted Answer

B. The swollen battery and heat generation indicate a physical battery failure, likely caused by internal damage from the drop. The built-in diagnostic tool reports 'Good' because it typically checks electrical parameters (voltage, charge cycles) rather than physical deformation or internal shorts. The drop likely compromised the battery's separator, leading to a thermal runaway risk regardless of software-reported health.

Answer

A

Answer

C

Answer

D

Question 3

A user reports that their workstation can access local network shares and printers but cannot access the internet. The technician pings the default gateway (192.168.1.1) successfully. The technician pings a public DNS server (8.8.8.8) and the request times out. Which of the following is the MOST likely cause?

Accepted Answer

The router's WAN connection is not functioning. The technician can ping the default gateway (192.168.1.1) successfully, confirming that the workstation's local IP configuration and Layer 2/3 connectivity to the router are correct. However, pinging the public DNS server 8.8.8.8 times out, which indicates that traffic is reaching the router but cannot exit to the internet. This points to a failure in the router's WAN connection (e.g., the modem or ISP link), as the router itself is reachable but cannot forward packets beyond the local subnet.

Answer

Incorrect DNS server configured on the workstation

Answer

The workstation's default gateway is misconfigured

Answer

The workstation's subnet mask is incorrect

Question 4

A user reports that they can access the company's internal web server by IP address (192.168.2.10) but not by its hostname (intranet.company.local). Other users on the same network can access the server by hostname without issues. The technician checks the user's network settings and sees that the DNS server is correctly set to the company's internal DNS server. Which of the following should the technician check NEXT?

Accepted Answer

Check the local hosts file for an incorrect entry. Since the user can reach the server by IP but not by hostname, and other users can resolve the hostname correctly, the issue is isolated to this specific workstation's name resolution. An incorrect entry in the local hosts file (C:\Windows\System32\drivers\etc\hosts) can override DNS lookups, mapping the hostname to a wrong or unreachable IP. This explains why the user fails to resolve 'intranet.company.local' while the DNS server setting itself is correct.

Answer

Check the default gateway configuration

Answer

Run ipconfig /flushdns to clear the DNS resolver cache

Answer

Change the DNS server to a public DNS server like 8.8.8.8

Question 5

A user reports that their wired desktop computer loses network connectivity for a few seconds at random times. The technician observes that when the issue occurs, the network activity LED on the integrated NIC turns off. The technician has already replaced the Ethernet cable, tested the switch port with another device (which works fine), and updated the NIC driver. Which of the following should the technician check NEXT?

Accepted Answer

B) Check the NIC's power management settings in Device Manager and disable 'Allow the computer to turn off this device to save power'. The symptom—random, brief connectivity loss with the NIC activity LED turning off—strongly suggests the operating system is powering down the NIC to save energy. Disabling the 'Allow the computer to turn off this device to save power' setting in the NIC's power management properties prevents the OS from entering a low-power state that drops the link. Since the cable, switch port, and driver have already been verified, this is the logical next step.

Answer

A) Replace the motherboard

Answer

C) Disable IPv6 on the NIC

Answer

D) Manually set the NIC speed and duplex to 10 Mbps Full Duplex

Question 6

A user reports that their smartphone's battery drains very quickly and the phone feels hot to the touch, even when the phone is idle. The phone is running the latest version of its operating system. Which of the following is the MOST likely cause?

Accepted Answer

A background app using excessive CPU resources. A background app using excessive CPU resources is the most likely cause because high CPU utilization generates significant heat and drains the battery rapidly, even when the phone is idle. The phone's operating system may not effectively throttle such rogue processes, especially if the app is poorly optimized or stuck in a loop. This symptom pattern—heat plus rapid discharge without active use—is classic for a runaway CPU process.

Answer

A faulty charging cable

Answer

A defective battery

Answer

Malware infection

Question 7

A user's Android tablet was dropped and the glass digitizer cracked, but the LCD display still shows images correctly. The user reports that touch input is unresponsive in several areas of the screen. Which of the following replacement procedures is MOST appropriate?

Accepted Answer

Replace the entire screen assembly (LCD and digitizer together). When the glass digitizer is cracked but the LCD display still functions, the digitizer (touch panel) is the damaged component. However, in most modern Android tablets, the digitizer is fused to the LCD as a single screen assembly, making it impractical or impossible to replace only the digitizer without damaging the LCD. Therefore, replacing the entire screen assembly (LCD and digitizer together) is the most appropriate procedure to restore full touch functionality.

Answer

Replace only the LCD display

Answer

Replace only the digitizer (touch panel)

Answer

Perform a touchscreen recalibration

Question 8

A user reports that they can access internal company servers using IP addresses (e.g., 192.168.1.100) but cannot browse the internet. The user can ping the default gateway (192.168.1.1) successfully. Other users on the same subnet have full internet access. The technician checks the user's IP configuration and sees that the IP address, subnet mask, default gateway, and DNS server (192.168.1.10) are all correct. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The user's browser proxy settings are configured to use an incorrect proxy server. Since the user can access internal servers by IP and successfully ping the default gateway, Layer 3 connectivity is intact. The inability to browse the internet while other users on the same subnet have full access points to a client-specific configuration issue. A misconfigured browser proxy setting (e.g., pointing to an incorrect or non-existent proxy server) would prevent HTTP/HTTPS traffic from reaching external destinations, even though DNS and IP routing are working correctly.

Answer

The DNS server is not resolving external domain names

Answer

The network cable is loose or faulty

Answer

The user's IP address is in the wrong subnet

Question 9

A user reports that their smartphone will not charge. The phone was working normally until the user plugged it into a generic car charger. Now, when connected to any charger, the phone displays the charging icon but the battery percentage does not increase over time. The technician has tested the phone with a known-good wall charger and cable, and the symptom persists. The phone is detected by a computer and can transfer files over USB. Which of the following components is MOST likely faulty?

Accepted Answer

Power management IC (PMIC). The Power Management IC (PMIC) is the component responsible for regulating the charging voltage and current, and for communicating the battery's charge state to the operating system. Since the phone shows a charging icon (indicating the PMIC is receiving power from the port) but the battery percentage does not increase (indicating the PMIC is not properly charging the battery), and the phone still works normally on USB data (ruling out a full logic board failure), the PMIC is the most likely faulty component. The generic car charger likely sent a voltage spike or improper power signal that damaged the PMIC's charging circuitry.

Answer

Battery

Answer

Charging port

Answer

System board (logic board)

Question 10

A user reports that their workstation cannot access the internet. The technician runs ipconfig and sees that the workstation has an IP address of 169.254.23.45 with a subnet mask of 255.255.0.0. The technician checks the network cable and link lights; they are normal. Which of the following is the MOST likely cause?

Accepted Answer

The DHCP server is not responding. The IP address 169.254.23.45 with a subnet mask of 255.255.0.0 is an Automatic Private IP Addressing (APIPA) address, which Windows assigns when a DHCP server cannot be reached. Since the link lights are normal and the cable is not faulty, the most likely cause is that the DHCP server is not responding, preventing the workstation from obtaining a valid IP address.

Answer

The Ethernet cable is faulty

Answer

The DNS server is misconfigured

Answer

The default gateway is incorrect

Question 11

A user's Android smartphone will not charge when plugged into the wall charger. The technician has already verified the charger and cable work with another phone, cleaned the charging port with compressed air, and performed a soft reset. Which of the following should the technician try NEXT?

Accepted Answer

Check the charging port for compacted debris with a flashlight and non-conductive tool. Since the charger and cable are verified working and a soft reset has been performed, the most likely remaining issue is physical debris deep inside the charging port that compressed air alone could not dislodge. Using a flashlight and a non-conductive tool (e.g., plastic or wooden pick) allows the technician to safely inspect and remove compacted debris without shorting the port's pins, which is a common cause of intermittent or failed charging on Android devices.

Answer

Replace the battery

Answer

Replace the charging port assembly

Answer

Perform a factory reset

Question 12

A user's smartphone running Android is unable to connect to any Wi-Fi network. The Wi-Fi toggle is grayed out and cannot be turned on. The technician has tried a soft reset and checked that Airplane Mode is off. Which of the following is the most likely cause?

Accepted Answer

Faulty Wi-Fi antenna or module. When the Wi-Fi toggle is grayed out and cannot be enabled, even after a soft reset and confirming Airplane Mode is off, it typically indicates a hardware-level failure. The most common cause is a faulty Wi-Fi antenna or module, as the operating system detects the hardware is not responding and disables the toggle to prevent user attempts. Software issues like corrupted settings or incorrect date/time would not prevent the toggle from being physically movable.

Answer

Corrupted network configuration

Answer

Incorrect date and time

Answer

Disabled Wi-Fi adapter in BIOS

Question 13

A user's iPhone is stuck on the Apple logo during startup and will not complete the boot process. The user has already performed a force restart (press and release Volume Up, then Volume Down, then hold the Side button) multiple times without success. Which of the following should the user do NEXT to resolve this issue?

Accepted Answer

Restore the device using iTunes or Finder. A force restart bypasses a temporary software hang, but if the iPhone remains stuck on the Apple logo, the boot process is failing due to a corrupted operating system or critical system file. Restoring the device via iTunes or Finder (or the Finder equivalent on macOS Catalina and later) reflashes the iOS firmware, replacing the damaged system partition and allowing the device to boot cleanly. This is the standard next step after a force restart fails to resolve a boot loop or startup freeze.

Answer

Replace the battery

Answer

Update the carrier settings

Answer

Perform a hard reset by holding the Home button and the Power button simultaneously

Question 14

A user's laptop powers on (fans spin, power LED on), but the built-in display remains black. The technician connects an external monitor to the laptop's video port, and the external monitor displays the desktop correctly. Which of the following is the MOST likely cause?

Accepted Answer

The LCD panel or backlight has failed. The laptop powers on (fans spin, power LED on) but the built-in display remains black, while an external monitor connected to the video port works correctly. This indicates that the GPU and video driver are functional, as they are able to drive the external display. The most likely cause is a failure of the LCD panel itself or its backlight (e.g., a faulty LED backlight, inverter, or display cable), since the internal display is the only component not working.

Answer

The laptop's video driver is corrupt

Answer

The RAM is faulty

Answer

The battery is not charging

Question 15

A user reports that they can access internal network resources and the internet by IP address, but cannot browse websites using domain names. Other users on the same network can browse the internet normally. Which of the following should the technician do FIRST?

Accepted Answer

Flush the DNS cache on the user's computer. The user can access resources by IP address but not by domain name, which indicates a DNS resolution failure. Since other users on the same network can browse normally, the issue is isolated to this specific workstation. Flushing the DNS cache (ipconfig /flushdns) clears any corrupted or stale DNS entries that may be preventing successful name resolution, making it the quickest and most logical first step.

Answer

Check the DHCP server configuration

Answer

Restart the DNS service on the domain controller

Answer

Replace the network cable

Question 16

A user's iPhone 12 has no sound from the speaker during phone calls, but the earpiece works normally. The user has confirmed that the volume is turned up and the silent switch is not enabled. The technician has performed a restart and updated iOS to the latest version. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The speaker grille is blocked or the speaker is faulty. The iPhone 12 uses a separate earpiece speaker for phone calls and a bottom-firing speaker for media and speakerphone. Since the earpiece works but the main speaker has no sound during calls, the issue is isolated to the bottom speaker grille being blocked (e.g., by debris or case obstruction) or the speaker itself being faulty. Restarting and updating iOS rules out software glitches, making hardware blockage or failure the most likely cause.

Answer

The Lightning port is clogged

Answer

The SIM card is damaged

Answer

The screen is cracked

Question 17

A user reports that they cannot access any websites through their web browser, but they can access shared files on the local network and can successfully ping 8.8.8.8 from the command prompt. The technician checks the IP configuration and finds the workstation has a valid IP address, subnet mask, and default gateway. The DNS server is set to 8.8.8.8. Which of the following is the MOST likely cause of the issue?

Accepted Answer

The web browser proxy settings are configured incorrectly, preventing internet access. The user can ping 8.8.8.8 (a public IP) and access local network shares, confirming that IP connectivity and DNS resolution to that specific server are working. However, they cannot browse websites, which typically use hostnames. Since the DNS server is set to 8.8.8.8 and pinging that IP succeeds, the issue is not DNS resolution itself but rather the web browser not using the correct network path. Incorrect proxy settings in the browser can cause it to send requests to a proxy server that is unreachable or misconfigured, effectively blocking internet access while other applications function normally.

Answer

A firewall rule is blocking all outbound traffic on ports 80 and 443

Answer

The DNS suffix search order is misconfigured

Answer

The ARP cache is corrupted, preventing the workstation from communicating with the default gateway

Question 18

A workstation has an APIPA address beginning with 169.254 after being moved to a new office. Other users in the office can access the network. What is the most likely issue?

Accepted Answer

The workstation did not receive an address from DHCP. The APIPA address (169.254.x.x) is automatically assigned by the operating system when a DHCP server is unreachable. Since other users in the office can access the network, the DHCP server is functioning, so the issue is specific to this workstation's inability to obtain a DHCP lease—likely due to a faulty cable, port, or NIC configuration.

Answer

The printer driver is missing

Answer

The monitor refresh rate is unsupported

Answer

DNS resolution is working normally

Question 19

After a power outage, a desktop computer will not power on. The PSU fan does not spin, and no LEDs are lit. The technician tests the power supply with a PSU tester; all voltages are within spec. A multimeter reading at the motherboard's power button header shows 3.3V when the button is pressed. The power supply is also confirmed to work when tested in another system. What is the most likely cause?

Accepted Answer

The motherboard has failed. The motherboard has failed because the PSU passes all voltage tests and works in another system, yet the desktop shows no signs of power (no fan spin, no LEDs) when connected to this motherboard. The 3.3V reading at the power button header indicates the motherboard is receiving standby power and the button is functioning, but the motherboard is not completing the power-on sequence (pulling PS_ON# low) to start the PSU. This points to a failed motherboard, likely a short or damaged power regulation circuit.

Answer

The power supply is still faulty despite the tester showing good voltages

Answer

The power button is faulty

Answer

The BIOS has become corrupted

Question 20

A user's smartphone was accidentally dropped into a puddle of water. The user immediately removed the phone from the water and wiped it dry. They are now attempting to power it on, but the phone does not respond. Which of the following should the user do FIRST to maximize the chance of recovery?

Accepted Answer

Place the phone in a bag of uncooked rice for 24-48 hours before trying to power it on. Option A is correct because uncooked rice acts as a desiccant, absorbing residual moisture from the phone's internal components over 24-48 hours. This passive drying process minimizes the risk of short circuits or corrosion when power is applied, which is critical since water can cause conductive paths between circuits even after external wiping.

Answer

Immediately plug the phone into a charger to see if it still works

Answer

Use a hair dryer on high heat to dry the phone quickly

Answer

Press and hold the power button for 10 seconds to force a reset