According to the PMBOK® Guide, Project Schedule Management consists of a specific logical sequence of processes within the Planning Process Group. Once the Define Activities process is complete (resulting in the Activity List, Activity Attributes, and Milestone List), the project manager must determine how those activities relate to one another and how long they will take.

Sequence Activities: This is the process of identifying and documenting relationships among the project activities. It involves using the Precedence Diagramming Method (PDM) to define logical dependencies (Finish-to-Start, Start-to-Start, etc.) so that a project schedule network diagram can be created.

Estimate Activity Durations: This is the process of estimating the number of work periods needed to complete individual activities with estimated resources. This must happen before the final schedule can be developed, as the total duration is a result of the individual activity estimates and their logical sequence.

The standard flow of Schedule Planning is:

Plan Schedule Management

Define Activities

Sequence Activities 4. Estimate Activity Durations 5. Develop Schedule

Why other options are incorrect:

Option B: Control Schedule is a Monitoring and Controlling process. It cannot be performed immediately after Defining Activities because the baseline schedule has not yet been created.

Option C: While Develop Schedule is a subsequent process, you cannot accurately develop a schedule until the activities have been sequenced and their durations have been estimated. Control Schedule is also misplaced in the planning sequence.

Option D: " Review Activities " is not a formal PMI process. Furthermore, you cannot jump directly to Develop Schedule without first establishing the logical relationships (Sequence) and the time required (Estimate) for each activity.