- A
The customer is responsible for patching the OS on virtual machines but not for PaaS; however, the customer must patch the OS for Azure SQL Database.
Why wrong: This is incorrect. For PaaS services like Azure SQL Database, the underlying OS is managed entirely by Microsoft. Customers do not have access to the OS and are not responsible for patching it.
- B
Microsoft is responsible for managing and patching the operating system of the underlying infrastructure for PaaS services.
This is correct. With PaaS, Microsoft handles the underlying OS, including security patches, while the customer focuses on data and application security.
- C
Both the customer and Microsoft share equal responsibility for patching the OS in a PaaS model.
Why wrong: This is incorrect. In PaaS, Microsoft fully manages the OS layer; the customer does not share this responsibility. The shared model applies to data, identities, and endpoints, not the infrastructure OS.
- D
The cloud service provider partner (e.g., a managed service provider) is responsible for OS patches in PaaS.
Why wrong: This is incorrect. While a partner can be engaged for managed services, the default responsibility for OS patching in PaaS lies with Microsoft as the cloud provider, not a third-party partner.
Quick Answer
The answer is Microsoft, because in the shared responsibility model for PaaS OS patching, the cloud provider retains responsibility for the underlying infrastructure. Azure SQL Database is a Platform as a Service offering where Microsoft manages the host operating system, hypervisor, and physical hardware, while the customer is only responsible for data, access, and database-level configurations. This distinction is critical for the SC-900 exam, which frequently tests your ability to map responsibilities across IaaS, PaaS, and SaaS—often using OS patching as a trap to see if you confuse PaaS with IaaS, where the customer would handle the OS. A common memory tip is to remember that with PaaS, you patch the platform (your app and data), but the provider patches the plumbing (the OS and hardware). Think of it as “PaaS = Provider patches the OS, you patch the app.”
SC-900 Practice Question: Describe the concepts of security, compliance, and identity
This SC-900 practice question tests your understanding of describe the concepts of security, compliance, and identity. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 company uses Azure SQL Database, which is a Platform as a Service (PaaS) offering. The security team is reviewing the shared responsibility model and wants to know who is responsible for applying operating system patches to the underlying infrastructure that hosts the database. Who is responsible for this task?
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
Microsoft is responsible for managing and patching the operating system of the underlying infrastructure for PaaS services.
Azure SQL Database is a Platform as a Service (PaaS) offering where Microsoft manages the underlying infrastructure, including the operating system. In the shared responsibility model for PaaS, Microsoft is responsible for applying OS patches to the host servers, while the customer manages the database configuration and data. Therefore, option B correctly identifies Microsoft as responsible for OS patching in this context.
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 customer is responsible for patching the OS on virtual machines but not for PaaS; however, the customer must patch the OS for Azure SQL Database.
Why it's wrong here
This is incorrect. For PaaS services like Azure SQL Database, the underlying OS is managed entirely by Microsoft. Customers do not have access to the OS and are not responsible for patching it.
- ✓
Microsoft is responsible for managing and patching the operating system of the underlying infrastructure for PaaS services.
Why this is correct
This is correct. With PaaS, Microsoft handles the underlying OS, including security patches, while the customer focuses on data and application security.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Both the customer and Microsoft share equal responsibility for patching the OS in a PaaS model.
Why it's wrong here
This is incorrect. In PaaS, Microsoft fully manages the OS layer; the customer does not share this responsibility. The shared model applies to data, identities, and endpoints, not the infrastructure OS.
- ✗
The cloud service provider partner (e.g., a managed service provider) is responsible for OS patches in PaaS.
Why it's wrong here
This is incorrect. While a partner can be engaged for managed services, the default responsibility for OS patching in PaaS lies with Microsoft as the cloud provider, not a third-party partner.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the shared responsibility model for PaaS with IaaS, mistakenly believing that because Azure SQL Database runs on VMs, the customer must patch the OS, when in fact Microsoft abstracts and manages the entire host OS layer in PaaS.
Detailed technical explanation
How to think about this question
Under the hood, Azure SQL Database runs on a multi-tenant or isolated deployment of SQL Server on Windows Server VMs managed by Microsoft's fabric controller. Microsoft automatically applies OS patches via Azure Update Manager and coordinated maintenance windows, ensuring compliance with security baselines like the Microsoft Security Response Center (MSRC) updates. In a real-world scenario, if a critical OS vulnerability (e.g., CVE-2024-1234) is disclosed, Microsoft patches the host OS without customer action, while the customer must still apply SQL Server-level patches if using a non-PaaS deployment like SQL Server on Azure VMs (IaaS).
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
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
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.
- →
Describe the concepts of security, compliance, and identity — study guide chapter
Learn the concepts, then practise the questions
- →
Describe the concepts of security, compliance, and identity practice questions
Targeted practice on this topic area only
- →
All SC-900 questions
1,411 questions across all exam domains
- →
Microsoft Security, Compliance, and Identity Fundamentals SC-900 study guide
Full concept coverage aligned to exam objectives
- →
SC-900 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related SC-900 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Describe the capabilities of Microsoft Entra practice questions
Practise SC-900 questions linked to Describe the capabilities of Microsoft Entra.
Describe the capabilities of Microsoft security solutions practice questions
Practise SC-900 questions linked to Describe the capabilities of Microsoft security solutions.
Describe the capabilities of Microsoft compliance solutions practice questions
Practise SC-900 questions linked to Describe the capabilities of Microsoft compliance solutions.
Describe the concepts of security, compliance, and identity practice questions
Practise SC-900 questions linked to Describe the concepts of security, compliance, and identity.
SC-900 fundamentals practice questions
Practise SC-900 questions linked to SC-900 fundamentals.
SC-900 scenario practice questions
Practise SC-900 questions linked to SC-900 scenario.
SC-900 troubleshooting practice questions
Practise SC-900 questions linked to SC-900 troubleshooting.
Practice this exam
Start a free SC-900 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 SC-900 question test?
Describe the concepts of security, compliance, and identity — This question tests Describe the concepts of security, compliance, and identity — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Microsoft is responsible for managing and patching the operating system of the underlying infrastructure for PaaS services. — Azure SQL Database is a Platform as a Service (PaaS) offering where Microsoft manages the underlying infrastructure, including the operating system. In the shared responsibility model for PaaS, Microsoft is responsible for applying OS patches to the host servers, while the customer manages the database configuration and data. Therefore, option B correctly identifies Microsoft as responsible for OS patching in this context.
What should I do if I get this SC-900 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Last reviewed: Jun 11, 2026
This SC-900 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-900 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.