- A
Create an IAM user in the developer's account and share the access keys
Why wrong: This would require sharing long-term access keys, which is a security risk. It does not use temporary credentials and violates the principle of least privilege.
- B
Use S3 bucket policy with a condition for the external account's IAM user
Why wrong: While a bucket policy can grant access to an external IAM user, that user still uses long-term credentials. This is not as secure as using temporary credentials via role assumption.
- C
Use cross-account IAM roles with STS AssumeRole
This allows the external user to assume a role in the developer's account, obtaining temporary credentials. It does not require sharing long-term keys and provides fine-grained control.
- D
Use S3 access control lists (ACLs) with the external user's canonical user ID
Why wrong: ACLs are a legacy permission mechanism and require the external user's canonical ID, which involves sharing long-term identifiers. They are less secure and not recommended for cross-account access.
DVA-C02 Security Practice Question
This DVA-C02 practice question tests your understanding of security. 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.
A developer needs to grant temporary access to an Amazon S3 bucket for a user from a different AWS account. The developer wants to use the most secure method that does not require sharing long-term credentials. Which approach should the developer take?
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
Use cross-account IAM roles with STS AssumeRole
Option C is correct because using cross-account IAM roles with AWS Security Token Service (STS) AssumeRole allows the external user to obtain temporary, limited-privilege credentials without sharing any long-term access keys. This approach follows the principle of least privilege and eliminates the risk of exposed static credentials, as the temporary credentials automatically expire after a configurable duration (default 1 hour, max 12 hours).
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.
- ✗
Create an IAM user in the developer's account and share the access keys
Why it's wrong here
This would require sharing long-term access keys, which is a security risk. It does not use temporary credentials and violates the principle of least privilege.
- ✗
Use S3 bucket policy with a condition for the external account's IAM user
Why it's wrong here
While a bucket policy can grant access to an external IAM user, that user still uses long-term credentials. This is not as secure as using temporary credentials via role assumption.
- ✓
Use cross-account IAM roles with STS AssumeRole
Why this is correct
This allows the external user to assume a role in the developer's account, obtaining temporary credentials. It does not require sharing long-term keys and provides fine-grained control.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use S3 access control lists (ACLs) with the external user's canonical user ID
Why it's wrong here
ACLs are a legacy permission mechanism and require the external user's canonical ID, which involves sharing long-term identifiers. They are less secure and not recommended for cross-account access.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse S3 bucket policies with cross-account access, thinking a bucket policy alone can grant temporary credentials, when in fact bucket policies only authorize access based on the requester's existing (long-term) credentials and do not issue temporary tokens.
Detailed technical explanation
How to think about this question
Under the hood, the AssumeRole API call returns a temporary security token (AccessKeyId, SecretAccessKey, SessionToken) with a defined expiration, which the external user's application uses to sign S3 requests. The trust policy on the IAM role in the developer's account must explicitly grant the external account's IAM user or role permission to assume the role, and the external user must call STS:AssumeRole with the role ARN. A real-world scenario is a third-party data processor that needs to upload files to your S3 bucket for a limited time; using cross-account roles ensures that even if the external account is compromised, the temporary credentials cannot be used beyond their expiration.
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 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.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
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.
- →
Security — study guide chapter
Learn the concepts, then practise the questions
- →
Security practice questions
Targeted practice on this topic area only
- →
All DVA-C02 questions
1,616 questions across all exam domains
- →
AWS Certified Developer Associate DVA-C02 study guide
Full concept coverage aligned to exam objectives
- →
DVA-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Development with AWS Services practice questions
Practise DVA-C02 questions linked to Development with AWS Services.
Security practice questions
Practise DVA-C02 questions linked to Security.
Deployment practice questions
Practise DVA-C02 questions linked to Deployment.
Troubleshooting and Optimization practice questions
Practise DVA-C02 questions linked to Troubleshooting and Optimization.
DVA-C02 fundamentals practice questions
Practise DVA-C02 questions linked to DVA-C02 fundamentals.
DVA-C02 scenario practice questions
Practise DVA-C02 questions linked to DVA-C02 scenario.
DVA-C02 troubleshooting practice questions
Practise DVA-C02 questions linked to DVA-C02 troubleshooting.
Practice this exam
Start a free DVA-C02 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 DVA-C02 question test?
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: Use cross-account IAM roles with STS AssumeRole — Option C is correct because using cross-account IAM roles with AWS Security Token Service (STS) AssumeRole allows the external user to obtain temporary, limited-privilege credentials without sharing any long-term access keys. This approach follows the principle of least privilege and eliminates the risk of exposed static credentials, as the temporary credentials automatically expire after a configurable duration (default 1 hour, max 12 hours).
What should I do if I get this DVA-C02 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 →
Keep practising
More DVA-C02 practice questions
- A developer is troubleshooting an AWS Lambda function that is triggered by an S3 event. The function occasionally fails…
- A developer needs to call AWS APIs from application code running on EC2. Which credential source should the AWS SDK use…
- A developer needs to allow an IAM user in a different AWS account to assume a role in the developer's account. The role…
- A developer needs to grant an IAM role in Account B read-only access to objects in an S3 bucket in Account A. The bucket…
- An API Gateway HTTP API should allow access only to users authenticated by an external OIDC provider. Which authorizer t…
- A developer needs to allow an EC2 instance to read from a DynamoDB table. Which is the best practice to grant permission…
Last reviewed: Jun 11, 2026
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.