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: Medicine
[{'content': 'Early loss of bladder control is seen in \nSelect and explain. \nA. Conus medullaris, B. Cauda equina, C. Gullain bane syndrome, D. Amyotrophic lateral sclerosis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Conus medullaris Loss of bladder control is an early and marked feature of conus medullaris.", 'role': 'assistant'}]