A 28-year-old man who had rheumatic fever as a child comes to the physician's office because of fatigue and dyspnea for the past 4 months. An early diastolic sound followed by a low-pitched rumbling decrescendo diastolic murmur is present 4 cm left of the sternal border in the fourth intercostal space and is heard best with the patient in the left lateral decubitus position. Which of the following valve defects is most likely in this patient?
(A) Aortic regurgitation
(B) Aortic stenosis
(C) Mitral regurgitation
(D) Mitral stenosis
(E) Pulmonic regurgitation
(F) Pulmonic stenosis
(G) Tricuspid regurgitation
(H) Tricuspid stenosis
(A) Aortic regurgitation
(B) Aortic stenosis
(C) Mitral regurgitation
(D) Mitral stenosis
(E) Pulmonic regurgitation
(F) Pulmonic stenosis
(G) Tricuspid regurgitation
(H) Tricuspid stenosis