This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of health and disease, Subject name: Social & Preventive Medicine
Epidemiology of cholera in England was clasified by 
Select and explain. 
A. John Snow, B. Winslow, C. Chadwick, D. Howard huges
A: John Snow
Answer: A: John Snow 
Explanation: An english epidemiologist John Snow studied the epidemiology of cholera in London from 1848 to 1854. Ref : Park&;s Textbook of Preventive and Social Medicine; 23rd edition