Which of the following activities is most likely to require a fraud specialist to supplement...

Engaging a fraud specialist is most likely required when interrogating a suspected fraudster. This specific activity demands specialized skills in interviewing and understanding behavioral cues that are outside the typical expertise of internal auditors. The use of fraud specialists ensures that interrogations are conducted effectively and that the information obtained is reliable, without compromising legal or ethical standards.

The Institute of Internal Auditors (IIA) - International Standards for the Professional Practice of Internal Auditing