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
The ratio of the incidence of the disease among exposed and the incidence among non-exposed is called 
Select and explain. 
A. Odds ratio, B. Relative risk, C. Attributable risk, D. None of the above
B: Relative risk
Answer: B: Relative risk 
Explanation: "Relative risk" (RR) or risk ratio is defined as the ratio between the incidence of disease among exposed persons and incidence among the non exposed.Incidence among exposedIQ = --------------------------------------------- x 100Incidence among non-exposedThe case-control study cannot give relative risk but from the case-control study, we can derive odds ratio.