Secretion of the androgen by Leydig cells of testis is under the regulatory influence of

The target of $ICSH$ is

$A$ boy after attaining sexual maturity shows muscular growth,growth of facial and axillary hair,aggressive behavior,and a low pitch of voice. These changes are attributed to the . . . . . . hormone.

Androgens act on the $A$ and influence the male sexual behavior called $B$. These hormones produce $C$ effect on protein and carbohydrate metabolism. Choose the correct combination of $A, B$ and $C$.

Which of the following hormones influences libido?

The hormone which brings about characteristic changes in the male at puberty is called: