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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。
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