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
What's the type of sampling, if a random sample is taken from a characteristic population. eg. Hindus, Muslims, Christian etc- 
Select and explain. 
A. Simpe random, B. Stratified random, C. Systematic random, D. Cluster
B: Stratified random
Answer: B: Stratified random 
Explanation: Stratified random sample is deliberately drawn in a systematic way so that each poion of the sample represents corresponding strata of universe. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 913