This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Social & Preventive Medicine
Randomization is done to reduce ? 
Select and explain. 
A. Recall bias, B. Selection bias, C. Berksonian bias, D. Repoing bias
B: Selection bias
Answer: B: Selection bias 
Explanation: Selection bias Types of bias * Selection bias is a distoion in the estimate of association between risk factor and disease that results from how the subjects are selected for the study. * Information bias is due to systematic measurement error or misclassification of subjects on one or more variables, either risk factor or disease status. * Confounding -results when the risk factor being studied is so mixed up with other possible risk factors that its single effect is very difficult to distinguish. Ref: Park 24th edition