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: Anatomy
[{'content': 'All are true about the trigone on the base of the urinary bladder, except ? \nSelect and explain. \nA. Mucosa is loosely associated to the underlying musculature, B. Mucosa is smooth, C. It is lined by transitional epithelium, D. It is derived from the absorbed pa of the mesonephric duct', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Trigone of the urinary bladder is a small triangular area located at the base of the bladder with apex towards the lower side. The mucosa is firmly attached to the underlying musculature giving it a smooth texture.', 'role': 'assistant'}]