This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'In a coho study nonsmokers were found to have carcinoma lung. This indicates - \nSelect and explain. \nA. Smoking does not cause lung cancer, B. Etiology for lung Ca is multifactorial, C. Smoking is the only cause of lung cancer, D. Passive smoking also increases lung cancer', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Etiology for lung Ca is multifactorialo Smoking is not specific for lung cancer becausei) Not everyone who developed lung cancer has smoked --> Other etiological factors (other than smoking) are also involved in causation of lung cancer, i.e., etiology of lung Ca is multifactorial.Not everyone who smoke develops lung cancer.", 'role': 'assistant'}]