1. Which of the following is considered a non-renewable energy source? A) Solar energy B) Wind energy C) Natural gas D) Geothermal energy

The correct answer is C) Natural gas.<br /><br />Natural gas is a fossil fuel that is formed from the decomposition of organic matter over millions of years. It is considered a non-renewable energy source because it cannot be replenished on a human timescale. Once natural gas reserves are extracted and used, they cannot be replenished within a reasonable timeframe.<br /><br />On the other hand, solar energy, wind energy, and geothermal energy are considered renewable energy sources. Solar energy is derived from the sun's radiation, wind energy is generated from the movement of air, and geothermal energy is obtained from the heat within the Earth. These energy sources are naturally replenished and can be harnessed sustainably over time.