"Within a community of 1000 adults, an initial clinical examination reveals that 250 have hypertension, defined as a diastolic blood pressure greater than 90 mm Hg and a systolic blood pressure greater than 140 mm Hg. All adults are followed for five years. During this follow-up period, 50 additional adults develop hypertension; 15 of these individuals die within 2 years of diagnosis of coronary heart disease or a cerebrovascular accident. The point prevalence at the start of the study is:"

30%

32%

40%

25%