Answer: IAM Roles

IAM Roles are the secure way to use AWS API from EC2 instances because: - **IAM Roles** provide temporary security credentials that are automatically rotated - They don't require storing long-term credentials (access keys/passwords) on the EC2 instance - Roles can be assumed by the EC2 instance service, eliminating the need to manage credentials - Temporary credentials reduce the risk of credential exposure - AWS automatically manages the credential lifecycle **Why other options are less secure:** - **IAM Users**: Require long-term access keys that must be stored on the instance - **IAM Groups**: Are containers for users, not credentials themselves - **IAM Policies**: Define permissions but don't provide credentials The AWS documentation confirms that IAM roles are intended to be assumable by anyone who needs them and provide temporary security credentials dynamically.

Author: Ritesh Yadav