10 Chikungunya virus infection was recently introduced into the Dominican Republic. During the first year after intro- duction, the virus has infected a total of 251,880 people in the Dominican...

Please provide rationale for question in attachment? Why is D the correct answer and the other options incorrect?

Extracted text: 10 Chikungunya virus infection was recently introduced into the Dominican Republic. During the first year after intro- duction, the virus has infected a total of 251,880 people in the Dominican Republic, which has a population size of 10.4 million people. Infection by the chikungunya virus is rarely fatal. Which of the following is correct? a. The incidence of chikungunya infection is 251,880 per year b. The prevalence of chikungunya infections is 251,880 c. The mortality rate of chikungunya is 24.2 per 1,000 person d. The 1-year cumulative incidence of chikungunya is 24.2 per 1,000 persons e. The cumulative survival from chikungunya infections is 24.2 per 1,000 persons