Create a Bucket on AWS S3

Answer - B.

Objects stored in your bucket before you set the versioning state have a version ID of null.

When you enable versioning, existing objects in your bucket do not change.

What changes is how Amazon S3 handles the objects in future requests.

Option A is incorrect because the version ID for file1 would be null.

Option B is CORRECT because the file1 was put in the bucket before the versioning was enabled.

Hence, it will have a null version ID.

The file2 will have two version IDs, and file3 will have a single version ID.Option C is incorrect because file2 cannot have a null version ID as the versioning was enabled before putting it in the bucket.

Option D is incorrect because once the versioning is enabled, all the files put after that will not have a null version ID.

But file1 was put before versioning was enabled.

So it will have null as its version ID.For more information on S3 versioning, please visit the below link.

http://docs.aws.amazon.com/AmazonS3/latest/dev/Versioning.html

In AWS S3, versioning can be enabled for a bucket to preserve, retrieve, and restore every version of an object stored in the bucket. Versioning can help you to protect against accidental overwrites, deletions, and malicious actions.

For the given scenario, assuming versioning is enabled on the bucket mybucket, the following actions are performed:

1. An object named file1 is uploaded to the bucket mybucket.
2. file2 is uploaded to the bucket mybucket, but with the same key as file1.
3. file2 is uploaded again to the bucket mybucket, but with a different key.
4. file3 is uploaded to the bucket mybucket.

Based on these actions, the following are the possible outcomes:

A. There will be 1 version ID for file1, 2 version IDs for file2, and 1 version ID for file3. - This is not correct, as file2 was uploaded twice, so there should be 2 version IDs for file1.

B. The version ID for file1 will be null. There will be 2 version IDs for file2, and 1 version ID for file3. - This is the correct answer, as file2 was uploaded twice, so there should be 2 version IDs for file2.

C. There will be 1 version ID for file1, the version ID for file2 will be null, and there will be 1 version ID for file3. - This is not correct, as file2 was uploaded twice, so there should be 2 version IDs for file2.

D. All file version IDs will be null because versioning must be enabled before uploading objects to mybucket. - This is not correct, as versioning can be enabled after objects are uploaded to a bucket. However, if versioning is not enabled, then all objects will have a null version ID.

Therefore, the correct answer is B: The version ID for file1 will be null. There will be 2 version IDs for file2, and 1 version ID for file3.