Which gland produces fluid making up about 30% of semen?

• A. Seminal vesicles
• B. Bulbourethral glands
• C. Prostate gland
• D. Testes

Answer: (C)

The main idea is that semen is a mix from several glands, and the proportion each gland contributes helps identify which one matches “about 30%.” The prostate gland releases a milky, slightly alkaline fluid that accounts for roughly a fifth to a third of semen, which is about 20–30%—close to 30%. This prostatic fluid contains enzymes, zinc, citrate, and other components that help activate and protect sperm as they travel through the female reproductive tract.

In contrast, the seminal vesicles contribute the largest share of semen volume with fructose-rich secretions to nourish sperm, the bulbourethral glands provide a small amount of mucus for lubrication, and the testes mainly provide sperm cells rather than a significant fluid volume. So the gland whose secretions are around 30% of semen is the prostate gland.