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: Pharmacology
[{'content': 'Remission with SSRI or TCA patient again having relapse. There may be deficiency of ? \nSelect and explain. \nA. Pyridoxine, B. Cobalamine, C. Ascorbate, D. Retinol', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. is \'b\' i.e., Cobalamine "Subjects with vitamin B12 deficiency and depression may present with history of past episodes with spontaneous remission or response to treatment with antidepressants and later recognition or development B1,deficiency"', 'role': 'assistant'}]