BD的their有指代错误，怎么答案C的those就没指代错误？

frankzhiwei

GWD3-Q30:

Today’s technology allows manufacturers to make small cars more fuel-efficient now than at any time in their production history.

A.small cars more fuel-efficient now than at any time in their

B.small cars that are more fuel-efficient than they were at any time in their

C.small cars that are more fuel-efficient than those at any other time in

D.more fuel-efficient small cars than those at any other time in their

E.more fuel-efficient small cars now than at any time in

frankzhiwei

求解答~

bdsjb116

我觉得b和d后面的那个their 都可以指manufacturers或者cars
只有c连着读起来没有歧义。