What is the best solution to groundwater depletion?

Ground water depletion is one of the major problems. The best solution is to conserve water that we are having currently and to recycle those wasted water. water conservation can be done in many ways such as reduce the level of pumping the ground water, avoiding the use of chemicals, use of natural fertilizers, rain water saving, pumping water to the tanks from stored rain water in the ground, way of handling the water consuming jobs.

The answer is letter c