This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
Prevalence of a disease depends upon the following- 
Select and explain. 
A. Incidence, B. Duration, C. Both of the above, D. None of the above
C: Both of the above
Answer: C: Both of the above 
Explanation: .prevalence of a disease can be calculated as prevalence is the product of incidence and the mean duration of the illness. ref:parks textbook ,22nd edition,pg no 59