The correct option is D Hypothalamus
The neurosecretory cells of the hypothalamus, when stimulated, release hormones, called neurohormones via axons into the capillaries. The nurohormones are carried by the portal blood to the anterior lobe of the pituitary gland and stimulate the latter to release its hormones. On this account, such hypothalamic hormones are also called releaser hormones. Certain hypothalamic hormones inhibit the secretion of some pituitary hormones. These are termed inhibitory hormones or factors (IH or IF).