Correct Answer: Timber

Solution : The correct answer is timber.

Energy resources are divided into two types- Renewable and Non-Renewable. Renewable energy resources are the one which are not limited by their availability like solar energy, wind energy, geothermal energy, tidal energy etc. Virtually timber is also an renewable energy source because of its availability. While Non-renewable energy resources are limited by its availability and if not sustainably used it will soon exhaust. For example- Coal, Fossil fuels, Minerals, Natural gas etc.