Why do the executing and controlling phases of a project usually overlap?

Because the executing phase defines the project scope and the project goals, and controlling phase defines the tasks required to accomplish those goals.

B Because project work takes place during the executing phase: A project manager the project schedule, budget, scope, resources and assignments to determine the the project that worked well as work is being performed.

Because the executing phase identifies all the tasks required to achieve project $g$ the controlling phase estimates the time each task will take to complete and dete tasks that are dependent upon one another.

D Because project work takes place during the executing phase: A project manager the status of the project and takes corrective action as work is being performed.