Which statement describes a purpose of monitoring, measurement, analysis and evaluation according to ISO/IEC 27001?

Clause 9.1 requires:

“The organization shall evaluate the information security performance and the effectiveness of the information security management system.”

This is the central purpose of monitoring, measurement, analysis, and evaluation. Competence (B) is covered under Clause 7.2. Monitoring use of assets (C) and outsourced processes (D) may be done, but they are not the formal purpose described in the standard. Instead, performance evaluation ensures the ISMS continues to meet intended outcomes and supports continual improvement.

Thus, the verified purpose is A: To evaluate information security performance.