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
Population attributable risk is defined as:- 
Select and explain. 
A. Incidence of disease among exposed is so many times higher as compared to that among non-exposed, B. So much disease can be attributed to exposure, C. If risk factor is modified or eliminated, there will be so much annual reduction in incidence of disease in the given population, D. None of the above
C: If risk factor is modified or eliminated, there will be so much annual reduction in incidence of disease in the given population
Answer: C: If risk factor is modified or eliminated, there will be so much annual reduction in incidence of disease in the given population 
Explanation: Population Attributable Risk (PAR) It is the incidence of disease (or death) in total population minus incidence of disease (or death) among those who were not exposed to suspected causal factor. It is useful as it provides an estimation of amount by which incidence of disease could be reduced in that population if the suspected factor was eliminated or modified. PAR is useful for National health programmes and policies.