Increasing the water temperature by adding hot water is called thermal heating, so the correct answer is d)
Answer: Thermal pollution
Explanation:
Thermal pollution is defined as rise in the temperature of the water body in which hot water is added. It degrades the quality of water due to any process which changes the ambient temperature of water.
This is mainly caused due to water used as coolant in the power plants which is released into the nearby water bodies.
Thus, increase in the temperature of water body due to addition of warmer water is known as thermal pollution.
