GWD 1 Q16 求助

cxn仔

Soaring television costs accounted for more than half the spending in the presidential campaign of 1992, a greater proportion than it was in any previous election.

1. a greater proportion than it was[CH1]
   
   
2. a greater proportion than
   
   
3. a greater proportion than they have been[CH2]
   
   
4. which is greater than was so[CH3]
   
   
5. which is greater than it has been[CH4]
   
   

[CH1]It不能指代前面的整句话


[CH2]Have时态错误，they指代不清


[CH3]Which指代不清，so没有指代


[CH4]Which指代错，has时态错

我觉得C中得they 指代costs没错啊 不过 完成时是不对， 但是如果是they 指代proportion不对的话 那A中得it应该可以啊

求助求助啊？ 是不是我哪里思考错误了？

HarrisZheng

要用than they did, 和accounted比较