The answer is a principal mismatch: the bucket policy grants access to the IAM role ARN, but the developer is authenticating with IAM user credentials. When you use access keys from an IAM user, AWS evaluates the request against the user’s identity, not any role the user might assume. Since the bucket policy explicitly allows only the role’s ARN, the request is denied because the principal (the IAM user) is not listed as an allowed entity. On the AWS Certified Developer Associate DVA-C02 exam, this scenario tests your understanding of how S3 bucket policies evaluate the requester’s identity versus the resource-based policy’s Principal element. A common trap is assuming that having permission to assume a role automatically extends to direct API calls made with user keys—it does not. Memory tip: “User keys need user ARN; role keys need role ARN—match the principal to the credential type.”
DVA-C02 Security Practice Question
This DVA-C02 practice question tests your understanding of security. 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 developer is troubleshooting access to an Amazon S3 bucket. The bucket policy allows access to the developer's IAM role, but the developer receives an Access Denied error when trying to upload objects. The developer is using an IAM user with access keys for API calls. 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.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The bucket policy allows the role ARN, but the developer is using user credentials
When using IAM user credentials, the bucket policy must grant access to the IAM user ARN, not the role ARN. The developer is using user credentials, so the bucket policy should reference the user, not the role.
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 developer’s IAM user does not have s3:PutObject permission
Why it's wrong here
Even if the user has permissions, the bucket policy must also allow the user; it's more likely the mismatch.
✗
The bucket policy does not include a Principal element
Why it's wrong here
Bucket policies must include a Principal element specifying who is allowed.
✗
The S3 bucket is in a different region from the developer's API endpoint
Why it's wrong here
Region mismatch would cause a different error (e.g., redirect), not Access Denied.
✓
The bucket policy allows the role ARN, but the developer is using user credentials
Why this is correct
The bucket policy references the role ARN, but the developer is using IAM user credentials; thus access is denied.
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.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→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 media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
What to study next
Got this wrong? Here's your next step.
Identify which DVA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Security — This question tests Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The bucket policy allows the role ARN, but the developer is using user credentials — When using IAM user credentials, the bucket policy must grant access to the IAM user ARN, not the role ARN. The developer is using user credentials, so the bucket policy should reference the user, not the role.
What should I do if I get this DVA-C02 question wrong?
Identify which DVA-C02 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
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 →
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 DVA-C02 practice question is part of Courseiva's free Amazon Web Services 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 DVA-C02 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.