Generate a sentence that answers this question: "A source of heat could be".

Answer: a radiator is a source of heat

Generate a sentence that answers this question: "Making a pie produces a".

Answer: cooking causes a chemical reaction

Generate a sentence that answers this question: "An alien creature is found on earth. Researchers discover that it will eat worms, insects and small rodents, but shuns bananas, leaves and cucumbers. Which of these could be true?".

Answer:
carnivores only eat animals