- A
The laptop's GPU is failing
Why wrong: If the GPU were failing, the external monitor would also show issues.
- B
The VGA cable is defective
Why wrong: The external monitor works, so the VGA cable is not the problem.
- C
The laptop's LCD panel or its video cable is damaged
Since the external display is fine, the internal panel or its connection is the likely culprit.
- D
The display driver is corrupt
Why wrong: A corrupt driver would affect both internal and external displays.
Question 406 of 1,020
Diagnosing a Distorted Laptop Display When External Monitor Works
This 220-1201 practice question tests your understanding of display devices. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A user reports that their laptop's built-in display shows distorted colors and horizontal lines, but when they connect an external monitor via VGA, the external display works perfectly. What is the most likely cause?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"most likely"Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Quick Answer
The answer is a damaged LCD panel or its video cable. This is correct because when a laptop display is distorted with colors and horizontal lines but an external monitor works fine, the graphics adapter is ruled out as the cause—it is successfully sending a signal to the external display. The fault must therefore lie in the internal display chain, specifically the LCD panel itself or the flexible video cable connecting it to the motherboard. On the CompTIA A+ Core 1 220-1201 exam, this scenario tests your ability to isolate hardware failures using the principle of component substitution; a common trap is to assume the GPU is bad when the issue is actually mechanical. Remember the memory tip: “If external is perfect, the internal path is suspect.”
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The laptop's LCD panel or its video cable is damaged
The correct answer is C because the external monitor works perfectly via VGA, which bypasses the laptop's internal LCD panel and its video cable. Distorted colors and horizontal lines on the built-in display, combined with a flawless external display, isolate the fault to the LCD panel assembly or the LVDS/eDP cable connecting the panel to the motherboard. The GPU and driver are shared between both displays, so they cannot be the cause when the external display functions correctly.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The laptop's GPU is failing
Why it's wrong here
If the GPU were failing, the external monitor would also show issues.
- ✗
The VGA cable is defective
Why it's wrong here
The external monitor works, so the VGA cable is not the problem.
- ✓
The laptop's LCD panel or its video cable is damaged
Why this is correct
Since the external display is fine, the internal panel or its connection is the likely culprit.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
The display driver is corrupt
Why it's wrong here
A corrupt driver would affect both internal and external displays.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume any display issue is caused by a failing GPU or driver, but the key diagnostic clue is that the external monitor works perfectly, which rules out the shared components and points to the internal display path. In CompTIA A+ troubleshooting, always isolate whether the problem is with the internal display assembly or the shared video subsystem by testing an external monitor.
Trap categories for this question
Command / output trap
If the GPU were failing, the external monitor would also show issues.
Detailed technical explanation
How to think about this question
Modern laptops use an embedded DisplayPort (eDP) or LVDS cable to connect the motherboard to the LCD panel; physical damage or loose connections in this cable cause signal degradation, resulting in color distortion and horizontal lines. The VGA port outputs an analog signal that is processed separately by the external monitor's own electronics, so it remains unaffected by internal cable or panel faults. In real-world scenarios, a common cause is a damaged eDP cable due to hinge wear from repeated opening and closing of the laptop lid.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the 220-1201 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Display Devices — study guide chapter
Learn the concepts, then practise the questions
- →
Display Devices practice questions
Targeted practice on this topic area only
- →
All 220-1201 questions
1,020 questions across all exam domains
- →
CompTIA A+ Core 1 220-1201 study guide
Full concept coverage aligned to exam objectives
- →
220-1201 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related 220-1201 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Mobile Device Hardware Servicing practice questions
Practise 220-1201 questions linked to Mobile Device Hardware Servicing.
Mobile Device Connection Methods practice questions
Practise 220-1201 questions linked to Mobile Device Connection Methods.
Mobile Device Accessories practice questions
Practise 220-1201 questions linked to Mobile Device Accessories.
Mobile Device Network Connectivity practice questions
Practise 220-1201 questions linked to Mobile Device Network Connectivity.
Mobile Device Application Support practice questions
Practise 220-1201 questions linked to Mobile Device Application Support.
Network Protocols practice questions
Practise 220-1201 questions linked to Network Protocols.
TCP & UDP Ports practice questions
Practise 220-1201 questions linked to TCP & UDP Ports.
Wireless Networking Technologies practice questions
Practise 220-1201 questions linked to Wireless Networking Technologies.
Network Services practice questions
Practise 220-1201 questions linked to Network Services.
Network Configuration Concepts practice questions
Practise 220-1201 questions linked to Network Configuration Concepts.
Common Networking Hardware practice questions
Practise 220-1201 questions linked to Common Networking Hardware.
IP Addressing practice questions
Practise 220-1201 questions linked to IP Addressing.
Practice this exam
Start a free 220-1201 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this 220-1201 question test?
Display Devices — This question tests Display Devices — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The laptop's LCD panel or its video cable is damaged — The correct answer is C because the external monitor works perfectly via VGA, which bypasses the laptop's internal LCD panel and its video cable. Distorted colors and horizontal lines on the built-in display, combined with a flawless external display, isolate the fault to the LCD panel assembly or the LVDS/eDP cable connecting the panel to the motherboard. The GPU and driver are shared between both displays, so they cannot be the cause when the external display functions correctly.
What should I do if I get this 220-1201 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Keep practising
More 220-1201 practice questions
- During a network cable installation, a technician needs to verify that a newly run Cat6 cable is properly terminated and…
- A user connects a 4K monitor to their laptop using a USB-C port. The monitor is detected, but the resolution is stuck at…
- A technician is troubleshooting a laptop that will not charge. The battery is removable, and the power adapter works on…
- A customer brings in a smartphone with a broken charging port. They want the port replaced. During disassembly, the tech…
- A user reports that their laptop's keyboard types random characters when certain keys are pressed. The laptop has not be…
- A technician is troubleshooting a laptop that shuts down randomly after a few minutes of use. The fan is spinning, and t…
Last reviewed: Jul 4, 2026
This 220-1201 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 220-1201 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.