This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of Control, Subject name: Social & Preventive Medicine
[{'content': 'Small pox vaccine was invented by? \nSelect and explain. \nA. Louis pasture, B. Edward Jenner, C. Paul Eugene, D. John snow', 'role': 'user'}, {'content': "Answer: B \nExplanation: ANSWER: (B) Edward JennerREF: Jawetz's 24th ed chapter 34Edward Jenner introduced vaccination for small pox with live cowpox virus in 1798.", 'role': 'assistant'}]