XDF蓝书P141,18

polkme

Intended primarily to stimulate family summer travel, the new airfare, which allows both an adult and a child to fly for the price of one ticket, and also shortens the advance-purchase requirement for family travel to a minimum of seven days rather than fourteen.
(A) and also shortens the advance-purchase requirement for family travel to a minimum of seven days rather than
(B) and also lessens the advance-purchase requirement for family travel to a seven-day minimum from
(C) also shortens the advance-purchase requirement for family travel to a minimum of seven days rather than that of
(D) also lessens the advance-purchase requirement for family travel to a seven-day minimum from
(E) also shortens the advance-purchase requirement for family travel to a minimum of seven days rather than

答案是E，请问C错在哪里？that of 为什么在这里不能使用？

shentuomi

这里七天和十四天是平行的
seven days rather than fourteen最为简洁，有效
“that of”给人一种感觉，好像什么东西属于fourteen一样，放在这里比较奇怪