Which structure of the male reproductive system from the following image stores the mature sperm before ejaculation?

A. Prostate: The prostate gland produces seminal fluid that nourishes and transports sperm but does not store mature sperm. Its main function is to contribute to the formation of semen.

B. Seminal Vesicle: The seminal vesicles produce a significant portion of the seminal fluid but do not store sperm. Instead, they provide nutrients for sperm and help form semen.

C. Epididymis: The epididymis is a coiled tube located at the back of each testis where sperm mature and are stored until ejaculation. It plays a crucial role in the maturation process of sperm.

D. Bulbourethral: The bulbourethral glands (or Cowper's glands) secrete a pre-ejaculate fluid that lubricates the urethra but do not store sperm.

A. Liver: The liver plays a role in detoxification and metabolism but is not involved in lymphocyte production.

B. Stomach: The stomach is part of the digestive system, not the immune system.

C. Small Intestine: The small intestine is involved in nutrient absorption and contains some lymphoid tissue (Peyer's patches) but is not the main site of lymphocyte production.

D. Thymus: The thymus is the organ where T-lymphocytes mature and are essential for the immune response.