An Amazon EC2 instance is running an application that uses Amazon Simple Queue Service (Amazon SQS) queues. A SysOps administrator must ensure that the application can read, write, and delete messages from the SQS queues.
Which solution will meet these requirements in the MOST secure manner?

A. Create an IAM user with an IAM policy that allows the sqs:SendMessage permission, the sqs:ReceiveMessage permission, and the sqs:DeleteMessage permission to the appropriate queues. Embed the IAM user's credentials in the application's configuration.
B. Create an IAM user with an IAM policy that allows the sqs:SendMessage permission, the sqs:ReceiveMessage permission, and the sqs:DeleteMessage permission to the appropriate queues. Export the IAM user's access key and secret access key as environment variables on the EC2 instance.
C. Create and associate an IAM role that allows EC2 instances to call AWS services. Attach an IAM policy to the role that allows sqs:* permissions to the appropriate queues.
D. Create and associate an IAM role that allows EC2 instances to call AWS services. Attach an IAM policy to the role that allows the sqs:SendMessage permission, the sqs:ReceiveMessage permission, and the sqs:DeleteMessage permission to the appropriate queues.