Which Amazon Elastic Compute Cloud feature can you query from within the instance to
access instance properties?

A.
Instance user data

B.
Resource tags

C.
Instance metadata

D.
Amazon Machine Image

Explanation:
Although you can only access instance metadata and user data from within the instance itself,
the data is not protected by cryptographic methods
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instancemetadata.html#instancedata-data-retrieval