Final answer:
The word 'confirms' is the best clue that a statement is a fact.
Step-by-step explanation:
The best clue that a statement is a fact is the word 'confirms'. When a statement is confirmed, it means that it has been verified and proven to be true. For example, if someone says 'Scientific research confirms that water boils at 100 degrees Celsius,' it indicates that this is a fact backed by scientific evidence.
Learn more about Identifying facts in statements