A developer is attempting to use the Amazon S3 PutObject API operation to upload an object to an S3 bucket that has default encryption enabled. The developer receives a 400 Bad Request error.
What is the most likely cause of this error?

A. The API operation cannot access the encryption key.
B. The HTTP Content-Length header is missing.
C. The object exceeds the maximum object size that is allowed.
D. The S3 bucket exceeds the maximum storage capacity that is allowed.