Global warming can be controlled by
(a) Increasing deforestation, reducing the efficiency of energy use
(b) Reducing deforestation, cutting down the use of fossil fuels
(c) Reducing deforestation, increasing use of fossil fuel
(d) Increasing deforestation, slowing down the growth of human population.

Hint: Deforestation, greenhouse gases like carbon dioxide and methane released by the burning of fossil fuels are the major causes of global warming.

Complete answer:
Global warming refers to an increase in the temperature in the earth's atmosphere than the normal range. It is caused by many human activities like the release of greenhouse gases like carbon dioxide and methane, deforestation and excess usage of fossil fuels. It is controlled by reforestation, reducing the use of fossil fuels, reducing deforestation, reducing the usage of substances that release greenhouse gases.

Additional Information: - The stratosphere of the earth consists of a layer called the ozone layer which is a protective shield from the harmful radiation from the sun
- Normally when sun rays reach the outermost layer of the atmosphere, clouds gases reflect about one-fourth of the sun rays and absorb some of it. the surface of the earth reflect heat in the form of IR radiation
- Because of greenhouse gases like carbon dioxide and methane, these rays again reflected back to the earth's surface resulting in an increase in temperature. This is called global warming.
- This can be reduced by reforestation, decreasing fossil fuels, and reducing greenhouse gases.
So, the correct answer is ' reducing deforestation, cutting down the use of fossil fuels'

Note: Normally the solar radiation falls on the surface and warms up and heat is released by the earth's surface in the form of IR rays that are escaped out. This is called the greenhouse effect. without this our earth's temperature would be -18°C rather than 15°C.