AWS Cost Explorer Hourly and Resource Granularity The Cost Explorer Hourly and Resource level granularity allows you to access hourly granularity for the past 14 days and resource level granularity for EC2 instances. The cost is $0.01 per 1,000 UsageRecords month. UsageRecords are defined as one line of usage. For example, one EC2 instance running for 24 hours will generate 24 distinct usage records at the hourly granularity. https://aws.amazon.com/aws-cost-management/pricing/

I would choose B: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/usage-reports.html Here's an example of some of the questions that you can answer when using Cost Explorer: How much am I spending on instances of each instance type?

B. AWS Cost Explorer is a tool that enables you to view and analyze your costs and usage. You can explore your usage and costs using the main graph, the Cost Explorer cost and usage reports, or the Cost Explorer RI reports. You can view data for up to the last 12 months, forecast how much you're likely to spend for the next 12 months, and get recommendations for what Reserved Instances to purchase. You can use Cost Explorer to identify areas that need further inquiry and see trends that you can use to understand your costs. https://docs.aws.amazon.com/cost-management/latest/userguide/ce-what-is.html

Ans is B