This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Physiology
[{'content': 'PGs in semen is secreted by \nSelect and explain. \nA. Prostate, B. Seminal vesicle, C. Sperms, D. Testes', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The seminal vesicles secrete a significant propoion of the fluid that ultimately becomes semen. Lipofuscin granules from dead epithelial cells give the secretion its yellowish color. About 50-70% of the seminal fluid in humans originates from the seminal vesicles, but is not expelled in the first ejaculate fractions which are dominated by spermatozoa and zinc-rich prostatic fluid.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-419', 'role': 'assistant'}]