The correct answer is A. water. That's because water's chemical composition is such that it can't be decomposed and turned into a fuel. Unlike Corn, sugar cane, and wood, it can't be used to power machines. The other ones are organic and can be used as biofuel, while wood can even be used in the form of coal as coal is nothing else than wood.I hope that my answer is helpful! Let me know if you need something more :)
