Please select the Amazon EC2 resource which cannot be t…

Please select the Amazon EC2 resource which cannot be tagged.

A.
images (AMIs, kernels, RAM disks)

B.
Amazon EBS volumes

C.
Elastic IP addresses

D.
VPCs

Explanation:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Using_Tags.html#tag-restrictions