Which statement correctly defines incidence and prevalence in epidemiology?

Which statement correctly defines incidence and prevalence in epidemiology?

• A. Incidence is the total number of existing cases at a given time; prevalence is the rate of new cases over a period.
• B. Prevalence is the rate of new cases over a period; incidence is the total number of existing cases at a given time.
• C. Incidence is the rate of new cases over a period; prevalence is the total number of existing cases at a given time.
• D. Both incidence and prevalence refer to the duration of a disease.

Answer: (C)