The correct answer is posterior pituitary.
ADH (AntiDiuretic Hormone) or Vasopressin is a peptide hormone which is produced in the hypothalamus. ADH is released from vesicles inside the cells of posterior pituitary into the circulation. ADH is released as a response of hyperosmolality of extracellular fluid. It increases the reabsorption of water in kidneys and constricts the blood vessels.
Oxytocin is also peptide hormone produced by the hypothalamus and released by the posterior pituitary. It has a role in sexual reproduction.