NO Link Vern is learning how to take a patient's blood pressure. He has his stethoscope pressed to their brachial artery, and he is just starting to release the pressure in the cuff. All of a sudden, he hears a knocking sound. What does this sound tell Vern?
OA Someone else is trying to get into the exam room,
OB His stethoscope is malfunctioning
OC. The patient is feeling nervous,
D. He has found the patient's systolic pressure,