Question: Within a small town in Spain whose population is 400, initial testing and examination revealed 20 persons with heart disease. Over the following 5 years, 80 more persons developed heart disease; 30 of these 80 persons died during that time. (assume no change in population size) The 5-year cumulative incidence of heart disease in the town is: A. 21 per 1,000 B. 21.1% C. 20% D. 7.5%