Answer: D) If we could get at least twenty-five percent of the entire senior class to agree with the change of venue for prom.
Explanation: Every other sentence is more or less a cause and effect. Mom screamed was the effect and the cause was due to the horror movie in front of her kids. The room goes silent, also an effect. Due to the principle with a clipboard. The final sentence has an effect, but no reason or cause. Therefore, it is incomplete.
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