This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and Reproduction, Subject name: Physiology
Which hormone inhibits FSH secretion in feedback- 
Select and explain. 
A. Testosterone, B. Progesterone, C. Inhibin, D. None
C: Inhibin
Answer: C: Inhibin 
Explanation: Ans. is 'c' i.e., Inhibin * LH is tropic for lyedig cells and the secretion of testosterone is under the control of LH. FSH is tropic for sertoli cells and stimulates sertoli cells to secrete inhibin and androgen binding protein (ABP). ABP binds testosterone, increasing its local concentration in the testes and thereby stimulating spermatogenesis.* Consistent with the phenomenon that the secretion of the target hormone inhibits is tropic hormone (negative feedback), testosterone inhibits LH secretion while estrogen (estradiol) and inhibin inhibit FSH secretion. Testosterone and estrogen have negative feedback at both pituitary and hypothalamic levels (GnRH), whereas inhibin exert negative feedback at pituitary level only.