SC-200 Respond to security incidents Practice Question
A Microsoft Defender XDR incident shows that a user's device has been communicating with a known malicious C2 server. The device is online and the user is actively working. You need to contain the threat with minimal business disruption. What should you do?
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
✓
Initiate device isolation from Microsoft Defender XDR
Initiating device isolation in Microsoft Defender XDR stops all network communication to and from the device while allowing the user to continue working locally, thus containing the threat with minimal business disruption. Option A is incorrect because disabling the switch port would require physical access to the network infrastructure and may not be feasible remotely. Option B is incorrect because shutting down the device remotely causes immediate disruption and loss of user productivity. Option C is incorrect because a full antivirus scan does not stop ongoing C2 communication and may allow the threat to continue spreading.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Remove the device from the network by disabling the switch port
Why it's wrong here
Disabling the switch port cuts the device's connectivity entirely, disrupting the active user's work and any shared services on that port. It is tempting because physical isolation reliably severs command-and-control traffic, and would be correct for an unmanaged device or a non-corporate switch, but Defender XDR offers device isolation preserving business continuity.
- ✗
Shut down the device remotely
Why it's wrong here
Shutting down the device severs command-and-control but also halts the user's active work and prevents remote forensic collection. It is tempting because powering off guarantees the malware stops running, and would be correct for an isolated, non-corporate endpoint, but Defender XDR's network isolation contains the threat while preserving investigation access.
- ✗
Run a full antivirus scan on the device
Why it's wrong here
A full antivirus scan only detects and remediates files; it does not sever the live command-and-control channel, so the device keeps communicating with the malicious server during the scan. It is tempting as a familiar remediation step, and would be correct after containment, but containment must precede scanning.
- ✓
Initiate device isolation from Microsoft Defender XDR
Why this is correct
Initiating device isolation from Microsoft Defender XDR contains the threat while the device stays online, satisfying the minimal-disruption constraint. Network isolation blocks all traffic except Defender XDR communication, so the user's session persists and the C2 channel is severed without wiping or powering off the endpoint.
Go deeper
Related to this question
About these practice questions
This SC-200 question is part of Courseiva's 1,303-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SC-200 practice question is part of Courseiva's free Microsoft 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 SC-200 exam.