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': 'Decreased level of serum Vit B6 is seen in \nSelect and explain. \nA. CRF, B. INH therapy, C. CHF, D. Alcohol', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]