question: What sentence would provide a factual answer to this question: "What will become magnetic in an electromagnet if the battery becomes active?"

answer: if battery in an electromagnet is active then the nail in the electromagnet will become magnetic

question: What sentence would provide a factual answer to this question: "Which of these could contribute to a species' demise?"

answer: the decrease of something required by an organism has a negative impact on that organism 's survival

question: What sentence would provide a factual answer to this question: "Plants would be unable to stand if they lacked"

answer:
a stem is a source of support for a plant