This AZ-400 practice question tests your understanding of design and implement build and release pipelines. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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.
You have a YAML pipeline that uses a multi-stage build. You want to cache the restored NuGet packages across builds to improve performance. Which caching strategy should you use?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Use the Cache@2 task with key: 'nuget | "$(Agent.OS)" | packages.lock.json', path: '$(System.DefaultWorkingDirectory)/packages'
Option A is correct because the Cache@2 task is the recommended way to cache NuGet packages in Azure Pipelines. By using a cache key that includes the agent OS and the packages.lock.json file, the cache is invalidated only when the lock file changes, ensuring restored packages are reused across builds. The path points to the NuGet global packages folder, which is typically $(System.DefaultWorkingDirectory)/packages when NUGET_PACKAGES is set.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Use the NuGetCommand@2 task with the -Cache argument.
Why it's wrong here
NuGetCommand does not have a -Cache argument for cross-build caching.
✗
Set the NUGET_PACKAGES environment variable to a custom path and rely on pipeline caching plugin.
Why it's wrong here
The environment variable is useful but caching must be explicitly configured.
✗
Use the DotNetCoreCLI@2 task with the --no-restore flag and manually copy packages.
Why it's wrong here
--no-restore skips restore, not caching.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The AZ-400 exam frequently reuses these exact scenarios with slightly different constraints.
✓Use the Cache@2 task with key: 'nuget | "$(Agent.OS)" | packages.lock.json', path: '$(System.DefaultWorkingDirectory)/packages'Correct answer▾✗Use the NuGetCommand@2 task with the -Cache argument.Wrong answer — click to see why▾
Why this is wrong here
NuGetCommand does not have a -Cache argument for cross-build caching.
✗Set the NUGET_PACKAGES environment variable to a custom path and rely on pipeline caching plugin.Wrong answer — click to see why▾
Why this is wrong here
The environment variable is useful but caching must be explicitly configured.
✗Use the DotNetCoreCLI@2 task with the --no-restore flag and manually copy packages.Wrong answer — click to see why▾
Why this is wrong here
--no-restore skips restore, not caching.
Analysis generated from the official AZ-400blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates may confuse the Cache@2 task's explicit key-path pairing with other NuGet-specific arguments or environment variables, assuming a simpler flag exists, when in fact Azure DevOps requires the Cache@2 task for reliable cross-build caching.
Trap categories for this question
Command / output trap
NuGetCommand does not have a -Cache argument for cross-build caching.
Detailed technical explanation
How to think about this question
Under the hood, the Cache@2 task uses Azure Blob Storage to store compressed archives of the specified path, keyed by the hash of the cache key expression. The packages.lock.json file, generated when using NuGet's PackageReference with restore lock files, provides a deterministic snapshot of all dependencies, making it an ideal cache key. In real-world scenarios, teams often combine this with a custom NUGET_PACKAGES environment variable to ensure the cache path matches the restored packages location, avoiding redundant downloads across multiple pipeline runs.
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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this AZ-400 question in full detail.
Design and implement build and release pipelines — This question tests Design and implement build and release pipelines — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Use the Cache@2 task with key: 'nuget | "$(Agent.OS)" | packages.lock.json', path: '$(System.DefaultWorkingDirectory)/packages' — Option A is correct because the Cache@2 task is the recommended way to cache NuGet packages in Azure Pipelines. By using a cache key that includes the agent OS and the packages.lock.json file, the cache is invalidated only when the lock file changes, ensuring restored packages are reused across builds. The path points to the NuGet global packages folder, which is typically $(System.DefaultWorkingDirectory)/packages when NUGET_PACKAGES is set.
What should I do if I get this AZ-400 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 →
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.
This AZ-400 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 AZ-400 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.