You want to define permissions for a role in an IAM policy. Which of the following configuration
formats should you use?

A.
An XML document written in the IAM Policy Language

B.
An XML document written in a language of your choice

C.
A JSON document written in the IAM Policy Language

D.
A JSON document written in a language of your choice

Explanation:
You define the permissions for a role in an IAM policy. An IAM policy is a JSON document written
in the IAM Policy Language.
http://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_terms-and-concepts.html