using precedence diagramming method, activity b must not start until activity a has been completed. moreover, the outcome of activity a cannot be used until 3 days after its completion. what is the correct description of the type of the relationship that exists between activites a and b? A.This relationship is an example of the rare but occasionally necessary Start-Finish relationship, SF-3d.B.This relationship is a standard Finish-Start relationship, FS, but the successor of B will have a 3 day lead.C.This relationship is a Finish-Start relationship, FS + 3d.D.This relationship mandates a dummy activity with a three-day duration following A.