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: Physiology
Testosterone secreted by, 
Select and explain. 
A. Leydig's cells., B. Somatotropic cells., C. Acidophilic cells., D. Gonadotropic cells
A: Leydig's cells.
Answer: A: Leydig's cells. 
Explanation: Ans:A. Leydig's cells.The hypothalamus sends a signal to pituitary gland to release gonadotrophic substances (follicle stimulating hormone and luteinizing hormone).Luteinizing hormone (LH) stimulates testosterone production.Testosterone is produced by gonads (by Leydig cells in testes in men & by ovaries in women).