What divides the testis into lobules?

Given below is a diagram of the $T.S.$ of a testis. Select the option which gives the correct identification of the function of cells labeled $A, B, C,$ and $D$ from the options given below.
$A$ - cells undergo spermatogenesis to produce spermatozoa.
$B$ - cell responsible for the development of male secondary sexual characters.
$C$ - heads of sperms remain attached to these cells.
$D$ - haploid male gamete.

In which of the following animals do the testes descend into the scrotum only during the breeding season?

Which of the following structures is found within the inguinal canal?

If Cowper's glands are removed,they will affect:

What is the function of the inguinal canal in humans?