What can be a main reason for a falling water table?

Correct answer: Excessive extraction of groundwater

The water table is the upper level of groundwater stored in the saturated zone beneath the surface. It falls when groundwater is pumped or withdrawn faster than rain and surface water can naturally infiltrate and recharge underground aquifers. Excessive extraction for irrigation, industry, or domestic use is therefore a major cause, making option A correct. Rainwater harvesting generally increases the supply available for recharge, planting trees can improve infiltration and reduce runoff in suitable conditions, and repairing leaks reduces unnecessary water loss. These three options are conservation or supportive measures rather than the main harmful cause described in the question. The governing green-skills concept is balancing groundwater withdrawal with natural and planned recharge so that water remains available for people and ecosystems.