Final answer:
The test data approach involves using auditor-controlled software to perform the same operations as the client's software using the same data files.
Step-by-step explanation:
The test data approach refers to auditors using auditor-controlled software to perform the same operations as the client's software using the same data files. This method allows auditors to independently process test data without relying on the client's computer system or application program.
For example, auditors may use their own computers and simulation software to simulate the client's computer system and run test data scenarios. This approach helps ensure the accuracy and validity of the audit process.
It's important to note that auditors should not use the client's software or rely on auditor-created data files to perform the test data approach.