This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pediatrics
What stimulates the gonads in male at 8 week to secret testosterone 
Select and explain. 
A. Inhibin from corpus luteum, B. GnRH from hypothalamus of baby, C. Placental HCG, D. All of above
C: Placental HCG
Answer: C: Placental HCG 
Explanation: Absence of Mullerian structures is suggestive of inefficient testosterone and dihydrotestosterone . Estimation of levels of anti -mullerian hormone and hcg stimulation tests are helpful in differentiating the two conditions.Children with vanishing testis will have low levels of anti-mullerian hormones and inapproprite stimulation to hcg. Reference: OP Ghai,essential paediatrics,8 th edition.page no 539