Quick Answer
The answer is Microsoft Defender XDR, the correct choice because it delivers integrated advanced threat detection across email, endpoints, and identities by correlating signals from Defender for Endpoint, Defender for Office 365, and Defender for Identity into a single incident queue. This unified Extended Detection and Response (XDR) approach enables automated remediation of multi-vector attacks, making it the only solution that provides both pre- and post-breach detection across these domains. On the Microsoft Cybersecurity Architect exam, this question tests your ability to distinguish between point solutions like individual Defender products and the holistic XDR platform—a common trap is selecting Microsoft Sentinel, which is a SIEM for broader log analysis rather than cross-domain threat correlation. Remember the memory tip: “XDR eXtends across Domains, while Sentinel Sits on top of logs.”
This SC-100 practice question tests your understanding of design solutions that align with security best practices and priorities. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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 security architect is designing a solution to detect and respond to advanced threats across email, endpoints, and identities. Which Microsoft security solution should they use?
Microsoft Purview
Why wrong: Purview is for data governance, not threat detection.
Microsoft Sentinel
Why wrong: Sentinel is a SIEM, not an XDR solution for endpoint/email.
Microsoft Defender XDR
Defender XDR provides integrated protection across email, endpoints, identities, and apps.
Microsoft Intune
Why wrong: Intune is for mobile device management, not threat detection.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Microsoft Defender XDR
Microsoft Defender XDR (Extended Detection and Response) is the correct solution because it provides unified pre- and post-breach detection, investigation, and response across email, endpoints, and identities. It correlates signals from Microsoft Defender for Endpoint, Defender for Office 365, and Defender for Identity into a single incident queue, enabling automated remediation of advanced multi-vector attacks.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Microsoft Purview
Why it's wrong here
Purview is for data governance, not threat detection.
Microsoft Sentinel
Why it's wrong here
Sentinel is a SIEM, not an XDR solution for endpoint/email.
Microsoft Defender XDR
Why this is correct
Defender XDR provides integrated protection across email, endpoints, identities, and apps.
Related concept
Read the scenario before looking for a memorised answer.
Microsoft Intune
Why it's wrong here
Intune is for mobile device management, not threat detection.
Common exam traps
The trap here is that candidates confuse Microsoft Sentinel (a SIEM) with Microsoft Defender XDR (an XDR), but Sentinel is a log aggregation and analysis tool requiring manual correlation, while Defender XDR provides native, automated cross-domain detection and response across email, endpoints, and identities.
Detailed technical explanation
Under the hood, Microsoft Defender XDR uses the Microsoft 365 Defender portal to fuse alerts from Defender for Endpoint (kernel-level sensors), Defender for Office 365 (email filtering and URL detonation), and Defender for Identity (on-premises Active Directory signals via domain controller agents) into a single incident graph. It leverages automated investigation and response (AIR) playbooks that can quarantine devices, block malicious IPs, or disable compromised accounts without manual intervention, reducing mean time to respond (MTTR) from hours to minutes.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Design solutions that align with security best practices and priorities — study guide chapter
Learn the concepts, then practise the questions
Design solutions that align with security best practices and priorities practice questions
Targeted practice on this topic area only
All SC-100 questions
969 questions across all exam domains
Microsoft Cybersecurity Architect study guide
Full concept coverage aligned to exam objectives
SC-100 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise SC-100 questions linked to Design solutions that align with security best practices and priorities.
Practise SC-100 questions linked to Design security operations, identity, and compliance capabilities.
Practise SC-100 questions linked to Design security solutions for infrastructure.
Practise SC-100 questions linked to Design a Zero Trust strategy and architecture.
Practise SC-100 questions linked to Design security solutions for applications and data.
Practise SC-100 questions linked to Evaluate GRC and security operations strategies.
Practise SC-100 questions linked to Design security for infrastructure.
Practise SC-100 questions linked to Design a strategy for data and applications.
Practise SC-100 questions linked to Recommend security best practices and priorities.
Practise SC-100 questions linked to SC-100 fundamentals.
Practise SC-100 questions linked to SC-100 scenario.
Practise SC-100 questions linked to SC-100 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Design solutions that align with security best practices and priorities — This question tests Design solutions that align with security best practices and priorities — Read the scenario before looking for a memorised answer..
The correct answer is: Microsoft Defender XDR — Microsoft Defender XDR (Extended Detection and Response) is the correct solution because it provides unified pre- and post-breach detection, investigation, and response across email, endpoints, and identities. It correlates signals from Microsoft Defender for Endpoint, Defender for Office 365, and Defender for Identity into a single incident queue, enabling automated remediation of advanced multi-vector attacks.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Same concept, more angles
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company wants to use Microsoft Defender XDR to detect and respond to advanced persistent threats (APTs). They have deployed Defender for Endpoint, Defender for Office 365, and Defender for Identity. What additional step is critical to correlate signals across these products?
mediumWhy A: Enabling the Microsoft Defender XDR unified experience in the portal is critical because it aggregates and correlates signals from Defender for Endpoint, Defender for Office 365, and Defender for Identity into a single incident queue and unified alert timeline. Without this step, each product operates in isolation, preventing cross-product detection of multi-stage APT attacks that span endpoints, email, and identity. The unified experience activates the Microsoft 365 Defender portal's correlation engine, which uses machine learning to link related alerts across domains into a single incident.
Keep practising
Last reviewed: Jun 24, 2026
This SC-100 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-100 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.