Which AWS service or feature will meet this requirement?

Explanations:

AWS Cost Explorer provides detailed insights into AWS spending, allowing users to visualize costs over time, including costs associated with On-Demand and Spot Instances. It offers various filters and grouping options to analyze spending effectively.

AWS Budgets allows users to set budgets and receive alerts when spending exceeds predefined thresholds, but it does not provide detailed visualizations of spending over time like Cost Explorer does.

Amazon CloudWatch is primarily used for monitoring and logging performance metrics and events for AWS resources, but it does not specifically provide cost visualization features.

AWS Cost Categories is used to categorize AWS costs for reporting purposes, but it does not provide the visual analytics capabilities that AWS Cost Explorer offers for analyzing monthly spending.