單項選擇題

如圖所示放大器的輸入電阻ri、輸出電阻ro和電壓放大倍數(shù)Au分別為()。

A.200kΩ,3kΩ,47.5倍
B.1.25kΩ,3kΩ,47.5倍
C.1.25kQ,3kΩ,-47.5倍
D.1.25kΩ,1.5kΩ,-47.5倍