27. Which statement BEST explains hormonal regulation of ovulation, including the hormones involved in ovulation induction?
(A) GnRH (Gonadotropin-Releasing Hormone) secretion stimulates estrogen release by the pituitary gland, directly inducing ovulation and supporting formation of the corpus luteum.
(B) GnRH stimulates the secretion of follicle-stimulating hormone (FSH) from the posterior pituitary, thereby promoting follicular growth in the ovary.
(C) Progesterone secreted from the corpus luteum enhances luteinizing hormone (LH) secretion and thereby directly triggers ovulation.
(D) Progesterone increases GnRH secretion from the hypothalamus during the follicular phase, thereby enhancing FSH release and triggering ovulation.
(E) Ovulation is triggered by a surge of LH released from the anterior pituitary following sustained high estrogen levels.