When surface of transpiration is submerged under water, then potential evapotranspiration is A. much more than evapotranspiration B. much less than evapotranspiration C. equal to evapotranspiration D. equal to or less than evapotranspi-ration

The correct answer is: B. much less than evapotranspiration.

Potential evapotranspiration (PET) is the maximum amount of water that can be evaporated from a surface under specific weather conditions. Evapotranspiration (ET) is the actual amount of water that is evaporated from a surface.

When the surface of transpiration is submerged under water, the rate of evaporation is greatly reduced. This is because the water on the surface forms a barrier that prevents water vapor from escaping into the atmosphere. As a result, PET is much less than ET.

Option A is incorrect because PET is always less than or equal to ET. Option C is incorrect because PET is not equal to ET when the surface of transpiration is submerged under water. Option D is incorrect because PET is not always equal to or less than ET.