You have an application that writes application logs to version enabled S3 bucket. Each object has multiple versions attached to it. After 60 days, the application deletes the objects in S3 through DELETE API on the object. However, in next month’s bill, you see charges for S3 usage on the bucket. What could have caused this?

Answer options:

A.DELETE API call on the object only deletes latest version.
B.DELETE API call on the object does not delete the actual object, but places delete marker on the object.
C.DELETE API call moves the object and its versions to S3 recycle bin from where the object can be restored till 30 days.
D.DELETE API for all versions of the object in version enabled bucket cannot be done through API. It can be only done by bucket owners through the console.

Answer: B
When versioning is enabled, a simple DELETE cannot permanently delete an object.
Instead, Amazon S3 inserts a delete marker in the bucket, and that marker becomes the current version of the object with a new ID. When you try to GET an object whose current version is a
delete marker, Amazon S3 behaves as though the object has been deleted (even though it has not been erased) and returns a 404 error.
The following figure shows that a simple DELETE does not actually remove the specified object. Instead, Amazon S3 inserts a delete marker.
 To permanently delete versioned objects, you must use DELETE Object versioned.
The following figure shows that deleting a specified object version permanently removes that object.
For information on how to delete versioned objects through API, refer to documentation here. 
https://docs.aws.amazon.com/AmazonS3/latest/dev/DeletingObjectVersions.html#delete-obj-version-enabled-bucket-rest
Option A is not true. DELETE call on an object does not delete the latest version unless the DELETE call is made with the latest version id.
Option C is not true. AWS S3 does not have to recycle bin.
Option D is not true. DELETE call on a versioned object can be made through API by providing the version id of the object’s version to be deleted.