Spermatogenesis is affected by which of the following?

Which one of the following is released by the Graafian follicle at the time of ovulation?

Given below are two statements:
Statement-$I$: Each primary oocyte gets surrounded by a layer of granulosa cells and is called a primary follicle.
Statement-$II$: At puberty, only $60,000-80,000$ primary follicles are left in each ovary.
In the light of the above statements, choose the most appropriate answer from the options given below:

What is the difference between a primary oocyte and a secondary oocyte?

Spermatogenesis is regulated by which of the following?

If the number of chromosomes in a somatic cell is $42$,what will be the number of chromosomes in the cuboidal epithelial cells of the seminiferous tubules?