You created network diagram for your project based on a chart when all of a sudden the person completing activity C says you must plan for a lag of 2 weeks after the completion of  the activity  before starting the next actvity. Which of the following is the FIRST thing to do?

A) Make Start, A,D,G,End the critical path in order to save the time

B)See if the duration of activity H can be shortened

C)Calculate project float after the insertion of the lag

D)Nothing, because the 2 weeks could be assigned to activity E