In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Q: Question: Which form of energy is produced when paper is burned? Answer: heat

A: Heat is produced when paper is burned.
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Q: Question: Formic acid is found in the secretions of? Answer: stinging ants

A: Formic acid is found in the secretions of stinging ants.
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Q: Question: What is the main cause of recent global warming? Answer: human beings

A:
Human beings is/are the main cause of recent global warming.
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