Which of the following medical specialties includes the study of the diseases and treatment of the male reproductive system?

The study of diseases and treatment of the male reproductive system is primarily a focus of urology. Urology is a branch of medicine that deals with the diagnosis and treatment of disorders related to the urinary tract in both males and females, as well as the male reproductive system. This specialty encompasses various conditions affecting the prostate, testes, and other components of the male reproductive anatomy.

While andrology is a subspecialty that specifically addresses male reproductive issues, such as infertility and erectile dysfunction, urology is the broader specialty that encompasses andrology, making it more encompassing in the context of the question. Gynecology, on the other hand, focuses on the female reproductive system, and endocrinology deals with hormone-related disorders affecting various glands in the body, which do not specifically target male reproductive issues. Thus, urology stands out as the correct answer since it directly covers the entirety of the male reproductive system and related health concerns.