This aquifer supplies one-third of the irrigation water in the united states
a. hetch-hetchy
b. verde mesa
c. quabbin
d. ogallala

ANSWER:

Ogallala aquifer supplies "one-third of the irrigation water" in the United States.

EXPLANATION:

The "Ogallala aquifer" is located in the "Great Plains of the United States" and therefore gives life to almost all fields of the US.The aquifer supplies water for one-third irrigation needs of the United States. The Ogallala is an underground reservoir and is very big in size and the agriculture production in the US is dependent on this aquifer. The aquifer is however depleting and water level in many areas has become very low. It is important for United States to protect and preserve this aquifer so that the agricultural production does not suffer.

The answer would be abrasion.