Concept:
Bio-drainage is a biological method of lowering the water table using plants.
Step 1: Some trees consume large quantities of groundwater through their roots.
Step 2: They release water into the atmosphere through transpiration.
Step 3: Planting such high water consuming trees can help reduce excess groundwater.
Step 4: This method is called bio-drainage.
Step 5: Therefore, the correct answer is bio-drainage.
\[
\boxed{\text{Bio-drainage}}
\]