The non-renewable source of energy is c. fossil fuels.
Explanation:
Fossil fuels like coal, oil, and natural gas are considered non-renewable because they take millions of years to form and are used up at a much faster rate than they are replenished.
Why other options are incorrect:
a. Wood: Wood is renewable because trees can regrow.
b. Sun: Solar energy is renewable because the sun’s energy is constantly replenished.
d. Wind: Wind is renewable as it is driven by the Earth’s rotation and atmospheric conditions.