Final answer:
Testosterone is critical for the development of male genitalia in the prenatal period, with its presence causing the differentiation of male sexual organs. The correct option is C.
Step-by-step explanation:
In the prenatal period, testosterone plays a crucial role in sexual development by promoting the development of male genitalia. During the second month after fertilization, the SRY gene on the Y chromosome triggers the secretion of testosterone.
This hormone, produced by Leydig cells in the embryonic testis, drives the development of male sexual organs. Without the presence of testosterone, the default development of reproductive organs would be female.
Testosterone ensures that males are born with male reproductive organs, though they remain immature and not yet capable of sperm production or testosterone secretion until puberty.