Review Question - QID 210842

A 7-year-old boy is brought to the pediatrician by his parents for a routine checkup. The parents note that the patient recently joined a baseball team and has had trouble keeping up with his teammates and gets short of breath with exertion. The patient has otherwise been healthy and has no known history of asthma or allergic reaction. Today, the patient’s temperature is 98.2°F (36.8°C), blood pressure is 112/72 mmHg, pulse is 70/min, and respirations are 12/min. The physical exam is notable for a heart murmur that decreases when the patient bears down. Additionally, the hand grip and rapid squatting maneuvers increase the severity of the murmur. Which of the following is likely heard on auscultation?