Final answer:
The best known hormone produced by the male sex glands is testosterone, which is responsible for the development of male sexual characteristics.
Step-by-step explanation:
The male sex hormone produced by the male sex glands, called testosterone, is the best known hormone in this class. Testosterone is responsible for the development of male primary and secondary sexual characteristics, such as the growth of the male reproductive system, deepening of the voice, and the development of facial hair and increased muscle mass. It is primarily produced in the testes and plays a crucial role in male reproduction and sexual development.