Answer: The endocrine system.
Step-by-step explanation: The endocrine system comprises endocrine glands that release hormones into the bloodstream that perform various functions targeting specific things in the body. The pituitary gland is a small pea-sized gland located in the brain below the hypothalamus and primarily releases growth hormone for growth, TSH for thyroid gland functioning, Prolactin for breast milk production, FSH and LH for menstruation, oxytocin for childbirth and ACTH for adrenal gland functioning. It also releases endorphins and enkephalins(pain relievers), Beta-melanocyte-stimulating hormone, and vasopressin (to conserve water and prevent dehydration).