B. Black box

Explanation:
The “Black box” approach is not a specific computer-assisted audit technique (CAAT). CAATs are specialized methods used by auditors to assess and analyze data within computer systems, including techniques like Integrated Testing Facility (ITF), System Control and Review Facility (SCARF), Parallel Simulation, and Snapshot. “Black box” testing generally refers to a type of software testing that does not provide insight into the inner workings of a system, making it unsuitable as an audit technique.