What is the location and function of the interstitial cells or Leydig cells?

Seminiferous tubules develop a central lumen after:

Which of the following is $NOT$ true for sustentacular cells (Sertoli cells)?

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.

Describe the location and function of the Scrotum and Epididymis.

The location and secretion of Leydig cells are: