Outsourced processes remain part of the audit universe because the organization retains accountability for risks, compliance, reporting, and service outcomes. The most accurate statement is that key controls are typically more difficult to audit because they are designed and managed externally. Internal audit may need service organization control reports, contractual audit rights, vendor evidence, site visits, management monitoring reports, or third-party assurance. Option A is wrong because outsourcing does not transfer accountability away from the organization. Option B is not generally true; independence is not automatically improved by outsourcing. Option D may be true in some cases, but it is not a general rule. Internal audit should ensure outsourced controls are visible, testable, and contractually enforceable. Therefore, Option C is correct.