C. Can be replenished by nature in a short period of time
Explanation:
Renewable, as a word, means that it is able to be replaced again. Renewable energy is energy that is able to be replaced quickly, and will never run out. Solar, biomass, geothermal, wind, and hydropower energy all can be reproduced again without the risk of running out, unlike fossil fuels.
B is wrong because mitochondria would likely absorb the stain even if it was dead.(And most cells that have been treated are dead anyway). C and D are just throwaway answers, you usually want to avoid the word "always" when drawing conclusions.
