Select the correct answer. Pacemakers maintain the heartbeat in people who suffer from certain defects. The function of an artificial pacemaker is to send electrical impulses that will contract the heart muscles and regulate the pumping of the heart. Which condition could be corrected by a pacemaker? A. The individual’s sinoatrial node ceases to function. B. The individual’s central nervous system fails to signal the heart to contract and relax. C. The individual’s arteries are blocked. D. The valves in the individual’s heart cease to function.