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: Gynaecology & Obstetrics
[{'content': 'First test to be done when a female presents with hirsutism is \nSelect and explain. \nA. Serum estradiol, B. Serum insulin, C. Serum testosterone, D. Serum prolactin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Serum testosterone should be first test to be done in females with hirsutism to rule out androgen producing tumors.', 'role': 'assistant'}]