There are two types of thirst and intracellular thirst and extracellular thirst. Extracellular thirst (dehydration) can be ruled out as it only requires water and salt to regenerate blood, at it's correct osmality. On the other hand, intracellular thirst (dehydration) can be corrected by drinking water alone. Therefore, the answer to this problem is intracellular thirst due to thirst for plain water.
