Which method meets the requirements?

A company is centralizing a large number of unencrypted small files rom multiple Amazon S3 buckets. The company needs to verify that the files contain the same data after centralization.

Which method meets the requirements?
A . Company the S3 Etags from the source and destination objects
B . Call the S3 CompareObjects API for the source and destination objects
C . Place a HEAD request against the source and destination objects comparing SIG v4 header
D . Compare the size of the source and destination objects

Answer: A

Explanation:

https://docs.aws.amazon.com/AmazonS3/latest/API/RESTCommonResponseHeaders.html