An internal data access policy is a set of rules and guidelines that define who, how, when, and why the users can access, use, share, or modify the data stored in a business application system, based on the data classification, sensitivity, and ownership.

Enforcing an internal data access policy is the most appropriate way to prevent unauthorized retrieval of confidential information stored in a business application system. This means that the organization implements and maintains effective controls to ensure that only the authorized users can access the confidential information, and that the access is logged and monitored for compliance and security purposes.

The other options are not the most appropriate ways to prevent unauthorized retrieval of confidential information stored in a business application system. They are either secondary or not essential for data access control.

The references for this answer are:

Risk IT Framework, page 28

Information Technology & Security, page 22

Risk Scenarios Starter Pack, page 20