Which of the following sentences is the most concisely worded?

A$.$ The project manager is in charge of furnishing specifications until such time as the project gets underway.

B$.$ Give the engineers the project manager's revised specifications before the project starts.

C$.$ Project managers have the capability of exercising their option to implement changes to the specifications before the official start date.

D$.$ All specifications should be provided by the project manager prior to the start of a project.