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单选题
Decibel is______.
A
the unit for measuring the intensity of sound
B
the pressure of radiating waves
C
the frequency of radiating waves
D
the seed of sound
参考答案
参考解析
解析：
细节题。文章第三段第一句提到“Intensity, or loudness, is the strength of the pressure of these radiating waves and is measured in decibels”，即分贝是用来计量声音强度的，A项“计量音量的单位”符合原意。
细节题。文章第三段第一句提到“Intensity, or loudness, is the strength of the pressure of these radiating waves and is measured in decibels”，即分贝是用来计量声音强度的，A项“计量音量的单位”符合原意。
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