Which of the following correctly identifies a related function of the prostate gland?

The prostate gland plays a crucial role in the male reproductive system, primarily by secreting a fluid that nourishes and transports sperm. This fluid, which is part of semen, helps to provide essential nutrients to the sperm cells, ensuring they remain viable and functional during their journey through the female reproductive tract. Additionally, this fluid contributes to the overall volume of semen, enhancing fertility by facilitating sperm movement.

The other functions mentioned in the other options are not related to the prostate gland. For instance, insulin production is primarily the function of the pancreas, while blood filtration is performed by the kidneys. Regulating sugar levels is also a function associated with pancreatic hormones, particularly insulin. Thus, option B accurately reflects the specific role of the prostate gland in the context of reproductive health.