A company wants to rightsize its Amazon EC2 instances. Which change reduces instance sizing with the least operational overhead?

Changing the size and type of EC2 instances based on utilization directly addresses rightsizing by matching instance resources to actual demand. This reduces waste and cost with minimal operational overhead, as it's a standard EC2 modification. Adding EC2 instances in another Availability Zone increases resilience, not rightsizing, and adds operational complexity. Converting to Savings Plans is a cost optimization strategy for existing usage, not a method for rightsizing the instances themselves. Reprovisioning with a larger instance type is the opposite of rightsizing and would increase costs and potentially operational overhead.