question: What sentence would provide a factual answer to this question: "Which of the following burns due to wax?"

answer: lighting a candle causes that candle to burn

question: What sentence would provide a factual answer to this question: "When the population of an organism decreases to the point that it is considered very likely it will soon reach zero, the organism is considered"

answer: if an organism dies then the population of that organism will decrease

question: What sentence would provide a factual answer to this question: "Eating and digesting a large meal is guaranteed to produce"

answer:
processes sometimes produce waste products