Which Technique Should the Nurse Implement When Performing the Allen

Which technique should the nurse implement when performing the Allen test on a patient to evaluate the adequacy of circulation in the radial artery?

A) Asks the patient to relax the hand by the side
B) Compresses only the ulnar artery to blanch the hand
C) Releases pressure on both arteries at the same time
D) Observes whether the color is returning to the hand, which indicates perfusion