This SCS-C02 practice question tests your understanding of infrastructure 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 company wants to restrict access to an Amazon S3 bucket so that only users from a specific AWS account can upload objects. Which policy mechanism should be used?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create a bucket policy with a condition that checks the aws:SourceAccount condition key.
Option D is correct because a bucket policy with a condition that checks the aws:SourceAccount condition key ensures that only requests originating from the specified account are allowed. Option A is wrong because IAM policies are attached to users/groups/roles, not to the bucket itself. Option B is wrong because S3 access control lists (ACLs) can grant access to other AWS accounts but do not support condition keys to restrict based on source account. Option C is wrong because a pre-signed URL grants time-limited access but does not restrict to a specific account.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
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 a bucket policy with a condition that checks the aws:SourceAccount condition key.
Why this is correct
This policy ensures that only requests from the specified account are allowed.
Related concept
Static NAT maps one inside address to one outside address.
✗
Attach an IAM policy to the bucket that denies access to all users except those from the allowed account.
Why it's wrong here
IAM policies are attached to identities, not to buckets.
✗
Generate a pre-signed URL for each upload request.
Why it's wrong here
Pre-signed URLs do not restrict by source account; they grant time-limited access to anyone with the URL.
✗
Configure the bucket ACL to grant access only to the allowed account's canonical user ID.
Why it's wrong here
ACLs do not support condition keys to restrict based on source account.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
Static NAT maps one inside address to one outside address.
PAT allows many inside hosts to share one public address using ports.
Inside local and inside global describe the private and translated addresses.
NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
→Identify inside and outside interfaces first.
→Check whether the scenario needs static NAT, dynamic NAT or PAT.
→Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
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.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related SCS-C02 NAT questions on configuration and troubleshooting.
Infrastructure Security — This question tests Infrastructure Security — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: Create a bucket policy with a condition that checks the aws:SourceAccount condition key. — Option D is correct because a bucket policy with a condition that checks the aws:SourceAccount condition key ensures that only requests originating from the specified account are allowed. Option A is wrong because IAM policies are attached to users/groups/roles, not to the bucket itself. Option B is wrong because S3 access control lists (ACLs) can grant access to other AWS accounts but do not support condition keys to restrict based on source account. Option C is wrong because a pre-signed URL grants time-limited access but does not restrict to a specific account.
What should I do if I get this SCS-C02 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related SCS-C02 NAT questions on configuration and troubleshooting.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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 SCS-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 SCS-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.