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 is a - 
Select and explain. 
A. Rate, B. Ratio, C. Propoion, D. mean
C: Propoion
Answer: C: Propoion 
Explanation: . the term "disease prevalence refers specifically to all current cases(old and new)existing at a given point in time or over a period of time in a given population.it is the total number of all individuals who have an attribute or disease at a paicular time or during a paicular period divided by the population at risk of having the attribute or disease at this point in time or midway through the period. ref:park&;s textbook of preventive and social medicine,22 nd edition ,pg no 58