Hi John,
Change management is an important concept to master in preparation for the PMP exam. Not only will you see a fair number of questions specifically on change management, but you will also likely encounter questions where understanding when a change request is required will help you eliminate incorrect answer choices (as is the case in your example).
1. Before the project has been baselined (project management plan has been approved) change requests are not required to modify any project artifact. See page 115 of the PMBOK® Guide.
2. Project artifacts that are placed in configuration control are recorded in the configuration management plan. Placing a project element in configuration control simply means that an approved change request is required for modification. See page 115 of the PMBOK® Guide.
3. Project baselines are always considered configuration elements. The rationale is that the baselines are the most fundamental aspect of the project, and if the baselines are not controlled, then a change management plan does not exist. Not having a change management plan would be contradictory to project management best practices. See page 115 of the PMBOK® Guide.
4. The project management plan is typically a controlled document. Unless the question suggests otherwise, we assume the project management plan is placed in configuration control.
5. Project documents are not typically placed in configuration control. Unless the question suggests otherwise, we assume that project documents are not considered configuration elements.
In the example you cite, the project schedule is a project document. Therefore, unless it is implied in the question that the project schedule has been placed in configuration control, then a change request is not required to be submitted prior to modification. If the schedule baseline where to be impacted, then an approved change request would be required to modify the schedule baseline.
Donald Terry, MBA, PMP, PMI-ACP
Full disclosure: I work for OSP International as an independent contractor