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
First test to be done when a female presents with hirsutism is 
Select and explain. 
A. Serum estradiol, B. Serum insulin, C. Serum testosterone, D. Serum prolactin
C: Serum testosterone
Answer: C: Serum testosterone 
Explanation: Serum testosterone should be first test to be done in females with hirsutism to rule out androgen producing tumors.