These questions are independently created for study purposes. They are not official AWS exam questions, actual exam questions, leaked questions, or exam dumps.
CLF-027
Which of the following best describes the main use case for AWS Cost Explorer?
Choices
Explanation and answer
Read the explanation and correct answer (spoiler — try answering first)
Correct answer: B. Analyzing trends in AWS usage charges and usage volume
Explanation
Cost Explorer visualizes AWS usage charges and usage volume, and supports cost analysis by service and by period.
Per-choice explanations
A. Storing the code of a Lambda function
Incorrect. It is not a description of Lambda code storage.
B. Analyzing trends in AWS usage charges and usage volume
Correct. Cost Explorer is used for cost analysis.
C. Stopping DNS queries in Route 53
Incorrect. It is not a service that stops DNS queries.
D. Resetting the password of an IAM user
Incorrect. IAM operations are performed in IAM.
Practical Use
AWS Cost Explorer is a free Management Console feature that visualizes and analyzes the cost and usage incurred in an AWS account. You can view daily and monthly trends, the breakdown by service, the breakdown by Region, the breakdown by linked account, and grouping by tags or cost allocation tags, all in charts and tables. You can see up to 13 months of historical data plus a 12-month forecast. On the exam, the question is typically phrased as "Which service analyzes trends in AWS usage charges and usage volume?" and Cost Explorer is the correct answer. Distractors include "resetting an IAM user password," "storing Lambda code," and "stopping DNS queries in Route 53," all of which lie outside the scope of cost management. This is a classic case where the exam is testing whether you have confused the role of the service. In practice, Cost Explorer is often used together with AWS Budgets. Cost Explorer is for "analyzing" past trends, while AWS Budgets is for sending "alerts" when a predefined budget is exceeded. CLF-C02 repeatedly tests the division of roles between these two services. For deeper cost optimization, it is common to start from a Cost Explorer report to check Savings Plans purchase recommendations, or to monitor the coverage and utilization of Reserved Instances.