Correct Option (B)
The corpus luteum is a temporary endocrine structure that forms in the ovary after the release of an ovum (egg) from the mature ovarian follicle during ovulation. It develops from the remnants of the ruptured follicle. Its primary function is to secrete the hormone progesterone, which is essential for preparing the uterine lining (endometrium) for potential embryo implantation and for maintaining early pregnancy. If fertilization and implantation do not occur, the corpus luteum degenerates.
Incorrect Options
The brain is the central organ of the nervous system and is not involved in the formation of reproductive endocrine structures like the corpus luteum.
The pancreas is a gland with both endocrine and exocrine functions, primarily involved in regulating blood glucose levels (producing insulin and glucagon) and secreting digestive enzymes. It does not contain a corpus luteum.
The spleen is a lymphatic organ involved in immune surveillance, blood filtration, and red blood cell recycling. It has no role in the female reproductive system or the formation of the corpus luteum.