题目内容：
根据下列短文，回答题。
The scientists are trying to find out if masks may or may not ________.
参考答案：
答案解析：
单选题：根据下列短文，回答题。The scientists are trying to find out if masks ma
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- 题目类型：单选题
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The scientists are trying to find out if masks may or may not ________.