Final answer:
The sentence that requires a citation is "Teenagers should put their phones down and concentrate on driving instead of who is texting them."
Step-by-step explanation:
The sentence that requires the use of a citation is: Teenagers should put their phones down and concentrate on driving instead of who is texting them.
When making a claim or stating a fact that is not common knowledge, it is important to provide a citation to support the statement. In this case, the statement that teenagers should put their phones down and concentrate on driving instead of who is texting them is an opinion or suggestion that requires a citation to back it up.
For example, a citation could be provided from a study or research conducted by a reputable source that highlights the dangers of distracted driving and how it is important for teenagers to focus on the road instead of their phones.
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