Answer: D. Wind
Explanation:
The use of coal, natural gas and petroleum as fuel after combustion will liberate immense amount of greenhouse gases into the atmosphere. These greenhouse gases will trap the heat energy from the sun which will lead to increase in the global temperature. This scenario is called as global warming.
Wind is a renewable source of energy, it is abundantly available in nature. The speed of the wind currents can be used to generate electricity by the motion of the wind turbine. This form of energy generation does not liberate any form of gas into the atmosphere. Therefore, will contribute least to the global warming.
