More money when we use both sides of paper.
A. will save
B. was saved
C. has saved
D. will be saved
网友回答
A. will save
B. was saved
C. has saved
D. will be saved
解析：考查动词的时态和语态。纸的正反两面都用的话，可以节省纸，当然也省下了更多的钱。Money在句中做主语，需要使用被动语态，排除A、C选项。另外，此句是when引导的时态状语从句，从句用了一般现在时，主句要用将来时，排除B。故选D。