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: Skin
[{'content': 'Treatment of choice in Pustuar psoriasis \nSelect and explain. \nA. Psorialin + UV therapy, B. Systemic steroid, C. Methotrexate, D. Estrogen', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Methotrexate', 'role': 'assistant'}]