DEA-C01 Data Operations and Support Practice Question
A company uses Amazon Kinesis Data Firehose to deliver streaming data to an Amazon S3 bucket. The data is then processed by a scheduled AWS Glue ETL job that loads it into an Amazon Redshift table. Recently, the Glue job has been failing with the error: 'S3ServiceException: Access Denied'. The Firehose delivery stream is configured with a prefix and error logging to the same S3 bucket. The Glue job uses the same IAM role that has s3:GetObject and s3:ListBucket permissions on the bucket. What is the most likely cause?
⚠ Common exam trap
DEA-C01 often tests the misconception that s3:GetObject alone is sufficient to read encrypted objects, ignoring the separate KMS permission requirement for SSE-KMS.
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 S3 bucket has default encryption enabled with AWS KMS (SSE-KMS), and the Glue job's IAM role lacks kms:Decrypt permission.
The Glue job's IAM role has s3:GetObject and s3:ListBucket, which are sufficient for reading objects from S3 in the absence of encryption. However, when the bucket uses SSE-KMS default encryption, reading an object requires the kms:Decrypt permission on the KMS key in addition to s3:GetObject. The 'Access Denied' error is the classic symptom of a missing kms:Decrypt grant, making option D the most likely cause.
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 Glue job expects a different data format than what Firehose writes.
Why it's wrong here
A format mismatch produces parsing or conversion errors during the Glue job, not an S3ServiceException reporting Access Denied, which originates from S3 authorisation checks. It is tempting because Firehose and Glue format mismatches are common, and format configuration would be the cause if the job failed while reading records.
- ✗
The Glue job's IAM role does not have s3:GetObjectVersion permission.
Why it's wrong here
s3:GetObjectVersion is needed only to read non-current object versions; the job reads current objects, so its absence cannot produce Access Denied here. It is tempting because versioned buckets do require that permission, and it would be the correct answer if the job explicitly retrieved archived object versions.
- ✗
The Glue job is using the wrong IAM role that does not have permissions to the S3 bucket.
Why it's wrong here
The stem states the Glue job already uses a role holding s3:GetObject and s3:ListBucket on the bucket, so a wrong or under-permissioned role contradicts the given facts. It is tempting because missing IAM permissions are the usual source of Access Denied, and role misconfiguration would be correct if the stem had not specified the permissions.
- ✓
The S3 bucket has default encryption enabled with AWS KMS (SSE-KMS), and the Glue job's IAM role lacks kms:Decrypt permission.
Why this is correct
With SSE-KMS default encryption, reading objects requires kms:Decrypt in addition to s3:GetObject. The Glue role holds only S3 permissions, so decryption fails and surfaces as Access Denied, despite the bucket and prefix configuration being correct.
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
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This DEA-C01 question is part of Courseiva's 1,321-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Amazon Web Services exam blueprint
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.