Quick Answer
The correct answers are Amazon Cognito and AWS IAM. Amazon Cognito provides user sign-up, sign-in, and access control for end-users, making it the ideal choice for customer-facing applications that need to authenticate individual users. AWS IAM, on the other hand, authenticates the caller’s identity using AWS Signature Version 4 signing, which is perfect for machine-to-machine or internal service calls where the requester already has AWS credentials. On the AWS Certified Solutions Architect Professional SAP-C02 exam, this distinction tests your ability to separate user authentication from service-to-service authorization—a common trap is assuming IAM is only for roles, not for direct API authentication. Remember the memory tip: Cognito for customers, IAM for internal machines.
This SAP-C02 practice question tests your understanding of design for new solutions. 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 is building a serverless application using AWS Lambda and Amazon API Gateway. They need to authenticate users. Which TWO services can be used for authentication?
AWS Security Token Service
Why wrong: STS issues temporary credentials, not direct authentication.
AWS IAM
IAM can authenticate users via API Gateway IAM authorization.
Amazon SQS
Why wrong: SQS is a messaging queue.
Amazon Cognito
Cognito provides user pools for authentication.
Amazon CloudFront
Why wrong: CloudFront is a CDN.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
AWS IAM
AWS IAM is correct because it can be used to authenticate users by attaching IAM authorization to API Gateway, allowing the API to verify the caller's identity via AWS Signature Version 4 signing. This is commonly used for machine-to-machine or internal service calls where the caller has AWS credentials.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
AWS Security Token Service
Why it's wrong here
STS issues temporary credentials, not direct authentication.
AWS IAM
Why this is correct
IAM can authenticate users via API Gateway IAM authorization.
Related concept
Read the scenario before looking for a memorised answer.
Amazon SQS
Why it's wrong here
SQS is a messaging queue.
Amazon Cognito
Why this is correct
Cognito provides user pools for authentication.
Related concept
Read the scenario before looking for a memorised answer.
Amazon CloudFront
Why it's wrong here
CloudFront is a CDN.
Common exam traps
The trap here is that candidates often confuse AWS STS (which issues temporary credentials) with an authentication service, or think SQS or CloudFront can handle authentication, when in fact only IAM and Cognito directly support user authentication for API Gateway in this context.
Detailed technical explanation
Amazon Cognito provides user pools for identity management and authentication, supporting OAuth 2.0, OpenID Connect, and SAML 2.0, and can issue JWTs that API Gateway validates via a Cognito authorizer. IAM authorization in API Gateway uses IAM policies and Signature Version 4 to authenticate requests, which is ideal for scenarios where the caller is an AWS service or has IAM credentials, such as in cross-account access or internal microservices.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Design for New Solutions — study guide chapter
Learn the concepts, then practise the questions
Design for New Solutions practice questions
Targeted practice on this topic area only
All SAP-C02 questions
1,746 questions across all exam domains
AWS Certified Solutions Architect Professional SAP-C02 study guide
Full concept coverage aligned to exam objectives
SAP-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise SAP-C02 questions linked to Design Solutions for Organizational Complexity.
Practise SAP-C02 questions linked to Design for New Solutions.
Practise SAP-C02 questions linked to Continuous Improvement for Existing Solutions.
Practise SAP-C02 questions linked to Accelerate Workload Migration and Modernization.
Practise SAP-C02 questions linked to SAA-C03 VPC.
Practise SAP-C02 questions linked to SAA-C03 S3 lifecycle policy questions.
Practise SAP-C02 questions linked to SAA-C03 RDS Multi-AZ questions.
Practise SAP-C02 questions linked to SAA-C03 IAM policy.
Practise SAP-C02 questions linked to SAA-C03 Route 53 failover questions.
Practise SAP-C02 questions linked to SAA-C03 CloudFront.
Practise SAP-C02 questions linked to SAA-C03 NAT gateway questions.
Practise SAP-C02 questions linked to SAA-C03 VPC endpoint questions.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Design for New Solutions — This question tests Design for New Solutions — Read the scenario before looking for a memorised answer..
The correct answer is: AWS IAM — AWS IAM is correct because it can be used to authenticate users by attaching IAM authorization to API Gateway, allowing the API to verify the caller's identity via AWS Signature Version 4 signing. This is commonly used for machine-to-machine or internal service calls where the caller has AWS credentials.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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
Last reviewed: Jun 24, 2026
This SAP-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 SAP-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.