Which Nursing Action Would Be Most Important After Adding 20

Which nursing action would be most important after adding 20 mEq potassium chloride to an I.V. bag of 1000 mL of 5% dextrose in water?

A) Rotate the bag gently.
B) Attach the tubing to the client.
C) Check the solution for particles.
D) Place the time-tape on the I.V.bag.