[求助] 请大家帮忙看看这两道GWD题的区别(GWD-24-Q20 vs GWD7-Q4)

elaineyll

GWD-24-Q 20:

According to a 1996 survey by the National Association of College andUniversity Business Officers, more than three times as many independentinstitutions of higher education charge tuition and fees of under $8,000 ayear than those that charge over $16,000.

A.than those that charge
B.than are charging
C.than to charge
D.as charge
E.as those charging

答案E，可是当我看过GWD7-Q4后，就不知道D为什么错了(D能不能理解为比较对象后者的主语被省略呢)，恳请NN点拨~~~
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GWD7-Q4:

Only seven people this century have been killed by the great white shark, the man-eater of the movies—less than those killed by bee stings.

A.movies—less than those
B.movies—fewer than have been
C.movies, which is less than those
D.movies, a number lower than the people
E.movies, fewer than the ones

答案B. E is wrong...

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