Question

which of the following best describes renewable energy?
depletable
sustainable
cheap
unsustainable

Explanation:

Renewable energy is energy that can be replenished naturally over time. "Sustainable" means able to be maintained at a certain rate or level, which aligns with the nature of renewable energy. "Depletable" and "unsustainable" are the opposite of what renewable energy is. While some renewable energy might be cheap, it's not the defining characteristic. The key is its sustainability.

Answer:

sustainable