Link tо Imаge Sоurce Cаse Study: A 42-yeаr-оld man visits his healthcare provider complaining of feeling thirsty all of the time, despite drinking nearly 10 liters of water per day. He also urinates frequently, which disturbs his workday and his sleep. Laboratory testing shows that his blood glucose levels are within the normal range. Further evaluation reveals that his kidneys are unable to conserve water properly because they are not receiving adequate stimulation from a hormone normally released by the posterior pituitary gland. Which hormone is most likely deficient in this patient?