Correct option (d) ovaries and anterior pituitary
Explanation :
Menstrual cycle is regulated by certain hormones, some of which are secreted by the pituitary gland. The pituitary gland is stimulated by releasing factors produced in the hypothalamus. The hormones produced by the pituitary gland influence the ovaries. The hormones secreted by the ovaries affect the walls of the uterus. It can be explained as: Gonadotropin releasing hormone (GnRH) also called Gonadotropin releasing Factor (GnRF), is secreted by the hypothalamus of the brain, which stimulates the anterior lobe of pituitary to release follicle stimulating hormone (FSH) and luteinising hormone (LH). FSH stimulates the ovarian follicles to produce estrogens during proliferative phase. LH stimulates the corpus luteum of the ovary to secrete progesterone.