Answer:
d. contains secretions from three different accessory glands
Explanation:
The semen is not only made up of sperm. It also consists of secretions coming from three accessory glands: seminal vesicles, prostate gland and bulbourethral gland.
The seminal vesicles secrete proteins, citric acid, sugar, etc. and this accounts for 2/3 volume of the semen. It has a white color that has a tinge of brown.
The prostate glad, on the other hand, secretes a fluid that accounts for 1/3 volume of the semen. This contains the Prostate Specific Antigen (PSA) that thins the semen.
The bulbourethral gland is also known as "Cowper's gland." This produces a secretion that ensures the sperm's motility.