选择题：20. 由于计算机只能接收数字量,所以在模拟量输入时需经( )转换。 (本题2.0分) A、 A/D

题目内容：

20. 由于计算机只能接收数字量,所以在模拟量输入时需经( )转换。 (本题2.0分)
A、 A/D转换器
B、双向可控硅
C、 D/A转换器
D、光电隔离器

参考答案：

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