AWS Certified SysOps Administrator – Associate (legacy) — Question 581

A company runs a web application that users access using the domain name www.example.com. The company manages the domain name using Amazon Route
53. The company created an Amazon CloudFront distribution in front of the application and would like www.example.com to access the application through
CloudFront.
What is the MOST cost-effective way to achieve this?

Answer options

• A. Create a CNAME record in Amazon Route 53 that points to the CloudFront distribution URL.
• B. Create an ALIAS record in Amazon Route 53 that points to the CloudFront distribution URL.
• C. Create an A record in Amazon Route 53 that points to the public IP address of the web application.
• D. Create a PTR record in Amazon Route 53 that points to the public IP address of the web application.

Correct answer: B

Explanation

Amazon Route 53 does not charge for queries to ALIAS records that point to CloudFront distributions, making an ALIAS record the most cost-effective option compared to a CNAME record which incurs standard query fees. Additionally, pointing records directly to the origin web application's IP address (A or PTR records) would bypass CloudFront entirely, failing to routing traffic through the distribution.