正解:C
According to the BABOK Guide, a change control system is a set of procedures that defines how changes to the approved requirements are initiated, evaluated, authorized, prioritized, planned, implemented, validated, and communicated. A change control system is necessary to manage the impact of changes on the requirements baseline, and to ensure that the changes are aligned with the business need and the solution scope1. Reference: 1: BABOK Guide, version 3, section 5.5.1, page 142.