A student nurse is precepting on the cardiac unit with the charge nurse. The charge nurse is educating the student about heart sounds and asks the student nurse to describe what causes the S1 sound. Which response by the student nurse reflects an understanding of cardiac sounds?

“It is caused by the mitral and tricuspid valves closing.” “It is caused by the mitral and pulmonic valves closing.” “It is caused by the pulmonic and aortic va...