Who maintains ownership of the audit report?

Comprehensive and Detailed In-Depth Explanation:

According to ISO 17021-1:2015, Clause 9.4.8 (Audit Reporting):

The certification body retains ownership of the audit report as it is responsible for the certification decision.

The auditee may receive a copy, but it does not own the report.

The audit team leader compiles the report but does not own it.

Thus, C is the correct answer.