Final answer:
Testosterone is the hormone responsible for developing male secondary sex characteristics such as facial hair, deep voice, and muscle strength. Option c.
Step-by-step explanation:
The hormone responsible for developing male secondary sex characteristics is testosterone. While luteinizing hormone (LH) and follicle-stimulating hormone (FSH) play critical roles in the reproductive systems of both sexes, it is LH that stimulates the testes to secrete testosterone.
Testosterone, in turn, triggers the development of characteristics such as facial hair, deep voice, and muscle strength. It also stimulates the process of spermatogenesis, which is the production of sperm.
In boys reaching puberty, the increase in testosterone leads to changes collectively known as secondary sexual characteristics. These changes include the deepening of the voice, growth of facial, axillary, and pubic hair, and the beginning of the sex drive.
Testosterone's role in these developmental milestones is crucial and defines many of the physical differences that emerge between males and females during adolescence. Option c.