A 55 year-old male patient is being evaluated for pulmonary rehabilitation. During a cycle ergometer cardiopulmonary stress procedure, the patient has a heart rate of 100/min and a respiratory rate of 20/min. He suddenly begins to complain of chest pain and severe shortness of breath. The respiratory therapist should

A. reduce the speed of the bike.
B. administer supplemental oxygen.
C. gradually reduce the workload and monitor closely.
D. terminate the procedure immediately.

Answer: D. terminate the procedure immediately.