Which gland produces a fluid that stimulates the motility of sperm?

The prostate gland plays a critical role in male reproductive health by producing a fluid that contributes to semen. This fluid is essential because it contains enzymes, citric acid, and other substances that help nourish and protect sperm. Importantly, the fluid from the prostate also helps to enhance sperm motility, enabling sperm to move more efficiently through the female reproductive tract to reach and fertilize an egg.

The seminal vesicle produces a significant portion of the seminal fluid, contributing to the bulk of semen but is primarily responsible for providing nourishment to the sperm rather than directly enhancing their motility. The bulbourethral gland, also known as Cowper's gland, secretes a pre-ejaculate fluid that helps lubricate the urethra and neutralize acidity but does not specifically stimulate sperm motility. The pituitary gland, while vital for regulating hormones related to reproduction, does not produce fluids that directly affect sperm motility. Therefore, the prostate gland is the correct choice, as its secretions are specifically tailored to promote the movement and viability of sperm during reproduction.