Final answer:
The cardiac diagnostic tool that requires the patient to exercise during the procedure is called a stress test.
Step-by-step explanation:
The cardiac diagnostic tool that requires the patient to exercise during the procedure is called a stress test (option a). During a stress test, the patient is made to exercise, usually on a treadmill or stationary bike, while their heart rate, blood pressure, and EKG readings are monitored. This test helps to assess the heart's performance under physical exertion and can detect any abnormalities in blood flow.