This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Demography, Subject name: Social & Preventive Medicine
[{'content': 'All of the following are true regarding confounding factor EXCEPT: \nSelect and explain. \nA. It is associated with exposure under investigation, B. It is distributed equally in study & control groups, C. It is associated both with exposure and disease, D. It is removed by matching in case control study', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) It is distributed equally in study & control groupsRef: K. Park 23rd ed./72', 'role': 'assistant'}]