Answer: Base the selection of Amazon EC2 instance types on past utilization patterns., Use Amazon S3 Lifecycle policies to move objects that users access infrequently to lower-cost storage tiers.

## Explanation **Rightsizing** refers to matching AWS resource capacity to actual workload requirements to optimize costs without compromising performance. ### Correct Answers: - **B: Base the selection of Amazon EC2 instance types on past utilization patterns** - This is classic rightsizing where you analyze historical usage data to select appropriately sized instances that match actual workload needs, avoiding over-provisioning. - **C: Use Amazon S3 Lifecycle policies to move objects that users access infrequently to lower-cost storage tiers** - This is rightsizing storage by moving data to more cost-effective storage classes based on access patterns. ### Incorrect Options: - **A: Switch from Amazon RDS to Amazon DynamoDB to accommodate NoSQL datasets** - This is database selection based on data model, not rightsizing existing resources. - **D: Use Multi-AZ deployments for Amazon RDS** - This is about high availability and disaster recovery, not cost optimization through rightsizing. - **E: Replace existing Amazon EC2 instances with AWS Elastic Beanstalk** - This is moving from IaaS to PaaS, which changes the service model but doesn't necessarily rightsize existing resources. Rightsizing focuses on optimizing the capacity of existing resources you're already using, typically through: - Analyzing utilization metrics - Selecting appropriate instance types - Using appropriate storage classes - Eliminating idle resources

Author: Ritesh Yadav