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
In Longitudinal studies, which of the following is true- 
Select and explain. 
A. Easy to conduct, B. Detects only one risk factor, C. Determines incidences of disease, D. Have increased bias
C: Determines incidences of disease
Answer: C: Determines incidences of disease 
Explanation: Longitudinal studies are useful: Study the natural history of the disease and its future outcome Identifying risk factors of disease Finding out incidence rate (refer pgno:70 park 23rd edition)