This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
A 35-year-old woman is admitted to the hospital with a complaint of shortness of breath. During physical examination it is noted that there is wide splitting in her S2 heart sound. Which of the following valves is/are responsible for production of the S2 heart sound? 
Select and explain. 
A. Mitral valve, B. Pulmonary and aortic, C. Aortic and mitral, D. Tricuspid
B: Pulmonary and aortic
Answer: B: Pulmonary and aortic 
Explanation: The S2 heart sound refers to the second (dub) heart sound. This sound is produced by the closure of the aortic and pulmonary semilunar valves. The closure of mitral/bicuspid and tricuspid valves produce the first S1 (lub) heart sound.