SAP-C02 Practice Question: Design Solutions for Organizational Complexity

Exhibit

Refer to the exhibit.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "lambda.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

Refer to the exhibit. A solutions architect is reviewing an IAM trust policy for a Lambda function's execution role. The function needs to access an S3 bucket in the same account. The trust policy is as shown. What is missing for the Lambda function to successfully assume the role?

⚠ Common exam trap

Many exam-takers confuse the trust policy (which controls who can assume the role) with the permissions policy (which controls what actions the role can perform), leading them to think the trust policy alone is sufficient for accessing resources.

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

✓

An IAM policy must be attached to the role granting permissions to the S3 bucket

The IAM trust policy only allows the Lambda service to assume the role, but it does not grant any permissions to access the S3 bucket. For the Lambda function to successfully read or write objects in the S3 bucket, an IAM permissions policy (e.g., s3:GetObject, s3:PutObject) must be attached to the role. Without this policy, the role has no effective permissions to perform actions on the bucket, even though the trust policy allows the role to be assumed.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
An IAM policy must be attached to the role granting permissions to the S3 bucket
Why this is correct
The trust policy allows Lambda to assume the role, but the role itself needs an IAM policy to grant S3 access.
✗
A service control policy must allow Lambda to assume roles
Why it's wrong here
SCPs are not required for service access.
✗
The S3 bucket must have a resource-based policy allowing the Lambda function
Why it's wrong here
Not necessary if the role has permissions via IAM policy.
✗
The trust policy must specify the Lambda function name
Why it's wrong here
The trust policy uses service principal, which is 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

SAP-C02 Practice Question: Design Solutions for Organizational Complexity

Exhibit

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

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