When Checking the Dynamic Balance of a Truck Driveshaft,an Initial

When checking the dynamic balance of a truck driveshaft,an initial spin up indicates the balance is out.Which of the following should be performed FIRST before proceeding?

A) remove any existing balance weights with a chisel
B) clamp one steel washer to the counterbalance position
C) remove the propeller shaft assembly
D) replace both the U-joints