In the urinogenital system of a rabbit, which of the following is present in the male but absent in the female?

The shared terminal duct of the reproductive and urinary system in the human male is

What is the functional unit of the human testis?

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.

Identify $A$ to $F$ in the diagram given below.

Which gland's secretion acts as a lubricant in the male reproductive system?