The sentence from the passage that best reveals the writer's beliefs about cheerleading injuries is: With proper supervision, training, and common sense, many of the more serious injuries can be avoided.
What is an opinion?
An opinion is the personal belief of an individual on a matter. An opinion is subjective. This means that it reflects the thoughts of the writer.
Of all the provided options, the third sentence shows the writer's personal views on ways in which cheerleading injuries can be avoided.
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https://brainly.com/question/1221103