Unauthorized modifications to scripts (D) pose the greatest risk because they can lead to unintended processing errors, security vulnerabilities, or fraudulent activities. Change management controls should be in place to prevent unauthorized script changes.

Other options:

Minor overrides not authorized (A) is a concern but does not pose as much risk as unauthorized script changes.

Bots incapable of learning (B) is a limitation but not a security risk.

Recording user interactions (C) raises privacy concerns but is not as critical as unauthorized script modifications.