Which of the following persons do NOT require prophylactic antibiotic treatment before a dental or surgical procedure?
A. A 32-year-old woman with a mitral valve prolapse associated with mitral regurgitation
B. A 70-year-old man with mild aortic stenosis caused by calcification of the aortic valve
C. A 37-year-old man who previously had a scarred mitral valve replaced with an artificial heart valve
D. A 55-year-old man with diabetes and angina pectoris