question: Given the fact "all animals breathe", what is the answer to "Inhaling O2 is a requirement of all"

answer: living animals

question: Given the fact "flowing liquid can push objects", what is the answer to "What is most likely to push objects?"

answer: rivers

question: Given the fact "coal is used to produce electricity by burning in coal-fire power stations", what is the answer to "This type of energy resource often results in particulates that are very toxic to breathe:"

answer: coal

question: Given the fact "An example of moisture is water vapor in the atmosphere", what is the answer to "What can you point to as an example of water vapor?"

answer:
a white puff in the sky that is shaped like a bird