Answer: By granting one role to another role

Role hierarchy in Snowflake is established by granting one role to another role, which creates a parent-child relationship. This is explicitly stated in Snowflake documentation and confirmed by the community discussion where all comments (with upvotes) unanimously select option C. Option A (assigning users to roles) manages user permissions but doesn't create role hierarchy. Option B (by default when a role is created) is incorrect as roles don't automatically have hierarchical relationships upon creation. Option D (transferring ownership) is not a valid method for establishing role hierarchy in Snowflake.

Author: LeetQuiz Editorial Team