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': 'Which of the following is not derivative of mesoderm? \nSelect and explain. \nA. Ureter, B. Gall bladder, C. Uterus, D. Epididymis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Gall bladder', 'role': 'assistant'}]