The correct answer to the question above is :
(c.) agriculture.
Agriculture is the greatest use of groundwater. Groundwater is a water found in the underground or beneath the Earth's surface, in the cracks and soil spaces.
Explanation:
Food and agriculture are the largest purchasers of water, requiring one hundred times more than we use for individual needs. Up to 70 % of the water we take from rivers and groundwater goes into irrigation, about 10% is used in residential applications and 20% in industry. Groundwater is the water today underneath Earth's outside in soil pore spaces and in the fractures of rock structures. A unit of rock or an unconsolidated alluvium is described as an aquifer when it can generate a usable quantity of water.