1. (2021高三上·浙江月考) 下列选项中，不能实现表达式1-1/3+1/5-1/7+1/9- 1/11计算的是（    ）

A	Sum=0 For i=1 To 12 Step 2 Sum =Sum+1/i Sum =-Sum Next i	B	Sum=1：t=1 For i=3 To 11 Step 2 Sum= Sum+t/i t =-t Next i
C	Sum=0 For i=1 To 11 Step 4 Sum =Sum+1/i Sum =Sum-1/(i + 2) Next i	D	Sum=1 For i=3 To 11 Step 2 t=(-1)^ (i\2) Sum= Sum+t/i Next i