A company sees an increase in Amazon EC2 costs on its latest bill. The billing team noticed unwanted vertical scaling of instance types for a few EC2 instances. A solutions architect must produce a graph comparing the last 2 months of EC2 costs and perform an in-depth analysis to identify the root cause with the LEAST operational overhead. How should the architect generate this information?

Cost Explorer is the most suitable tool for this scenario because it provides granular filtering capabilities, allowing for in-depth analysis of EC2 costs by instance type over custom time ranges with minimal operational overhead. It's designed for visualizing and analyzing cost and usage data directly within the AWS Management Console. AWS Budgets focuses on setting alerts and managing spending, not detailed cost analysis by instance type. The AWS Billing and Cost Management dashboard offers high-level overviews but lacks the granular filtering needed for an in-depth root cause analysis. AWS Cost and Usage Reports (CUR) combined with Amazon QuickSight would provide detailed analysis, but this approach involves significant operational overhead in setting up and configuring the CUR, S3 bucket, and QuickSight, which goes against the requirement of "LEAST operational overhead.