Final answer:
About two-thirds of the body's water is contained within the extracellular fluid, which includes the interstitial fluid and plasma.
Step-by-step explanation:
Extracellular fluid is the fluid that contains about two-thirds of the body's water. It surrounds and bathes all of the body's cells except for blood cells. The two primary components of extracellular fluid are the interstitial fluid, which surrounds cells that are not blood cells, and the fluid component of blood called plasma.