DEA-C01 Data Operations and Support Practice Question
Exhibit
Refer to the exhibit.
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:GetObject",
"s3:PutObject",
"s3:DeleteObject"
],
"Resource": "arn:aws:s3:::data-lake-bucket/*",
"Condition": {
"StringEquals": {
"s3:x-amz-server-side-encryption": "AES256"
}
}
},
{
"Effect": "Deny",
"Action": "s3:PutObject",
"Resource": "arn:aws:s3:::data-lake-bucket/*",
"Condition": {
"StringNotEquals": {
"s3:x-amz-server-side-encryption": "aws:kms"
}
}
}
]
}
```A data engineer applies the above S3 bucket policy to an S3 bucket used by a Glue ETL job. The Glue job writes objects to the bucket. Which of the following is true about the behavior of the policy?
⚠ Common exam trap
Candidates often assume an Allow statement with a broader scope can override a Deny, but AWS IAM policy evaluation strictly enforces that an explicit Deny always takes precedence over any Allow, making the policy effectively deny all actions that match the Deny condition.
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
✓
The policy denies all PutObject requests because the Allow and Deny statements are contradictory.
In AWS IAM policy evaluation, an explicit Deny always overrides any Allow. The policy has an Allow statement granting s3:PutObject for all principals, but a separate Deny statement explicitly denies s3:PutObject when the encryption condition is not aws:kms. Since the Deny applies to all PutObject requests (including those with no encryption or AES256), and the Allow does not include a condition to match only aws:kms, the Deny takes precedence and blocks all PutObject requests, making the policy effectively deny all PutObject operations.
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 policy allows PutObject with aws:kms encryption because the Allow statement is broader.
Why it's wrong here
The Allow only covers AES256, not aws:kms, and the Deny blocks anything that is not aws:kms.
- ✗
The policy allows PutObject with no encryption because the Deny only applies to PutObject.
Why it's wrong here
The Deny applies to any PutObject that does not use aws:kms, so no encryption is denied.
- ✓
The policy denies all PutObject requests because the Allow and Deny statements are contradictory.
Why this is correct
The Allow requires AES256, the Deny requires aws:kms; no request can satisfy both, and Deny overrides Allow.
- ✗
The policy allows PutObject with AES256 encryption and denies PutObject with aws:kms encryption.
Why it's wrong here
The Deny statement applies to all PutObject requests not using aws:kms, so AES256 is denied.
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 |
Go deeper
Related to this question
About these practice questions
Courseiva writes every DEA-C01 question from scratch — 1,711 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DEA-C01 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 DEA-C01 exam.