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': 'Which of the following drugs cause oligospermia ? \nSelect and explain. \nA. Leflunomide, B. D - Penicillamine, C. Methotrexate, D. Sulfasalazine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Sulfasalazine can cause a reversible infertility in males\xa0owing to changes in sperm number and morphology.', 'role': 'assistant'}]