AWS Certified Solutions Architect – Associate (SAA-C02) — Question 25

A solutions architect is designing an application for a two-step order process. The first step is synchronous and must return to the user with little latency. The second step takes longer, so it will be implemented in a separate component. Orders must be processed exactly once and in the order in which they are received.
How should the solutions architect integrate these components?

Answer options

• A. Use Amazon SQS FIFO queues.
• B. Use an AWS Lambda function along with Amazon SQS standard queues.
• C. Create an SNS topic and subscribe an Amazon SQS FIFO queue to that topic.
• D. Create an SNS topic and subscribe an Amazon SQS Standard queue to that topic.

Correct answer: A

Explanation

The correct answer is A because Amazon SQS FIFO queues ensure that messages are processed in the exact order they are received and exactly once, which meets the requirements of the application. Option B is incorrect as standard queues do not guarantee order or exactly-once processing. Options C and D involve SNS, which is not suitable for maintaining the order of messages as needed in this scenario.