Energy conservation means
a. slowing down a chemical change.
b. burning a fuel to release energy.
c. using fossil fuels to produce electricity.
d. reducing energy use.

d. reducing energy use

Explanation:

Reducing energy use will be a correct attribute for the conservation of energy. This is because of the fact that limitation in energy consumption will lead to securing of the available resources. For example the use of fossil fuels and the energy harnessed by them can be conserved by using alternative sources of energy like solar energy, wind and tidal energy. This will ensure the availability of fossil fuels for future generations.

more than, less

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