Answer: AWS Cost Explorer, AWS Compute Optimizer

**AWS Cost Explorer** and **AWS Compute Optimizer** are the correct services for identifying rightsizing opportunities for Amazon EC2 instances. **AWS Cost Explorer** helps analyze AWS costs and usage patterns, and it provides rightsizing recommendations based on historical usage data. **AWS Compute Optimizer** specifically analyzes resource utilization metrics of EC2 instances and provides recommendations for rightsizing to optimize performance and reduce costs. The other options are not designed for EC2 rightsizing: - **AWS Billing Conductor** is for customizing billing data and creating billing views - **Amazon CodeGuru** is for code quality and performance analysis - **Amazon SageMaker** is for machine learning model development and deployment

Author: Ritesh Yadav