What is the MOST accurate way to determine a project’s duration before execution？（）

A.by written and oral communication.
B.via a weekly status report.
C.through the formal chain of command.
D.with approved template forms.

A.To gain the client’s acceptance of the detailed design
B.To verify mutual understanding of project resources
C.To verify mutual understanding of the detailed project plan
D.To verify mutual understanding of targeted product performance
E.To verify mutual understanding of the tests that will be done after the product is completed

A.WBS （Work Breakdown Structure）.
B.cost benefit analysis.
C.requirements specifications.
D.narrative description of the work to be accomplished.