请教Prep2-25

There is a widespread belief in the United States and Western Europe that young people have a smaller commitment to work and a career than their parents and grandparents and that the source of the change lies in the collapse of the "work ethic."

(A) a smaller commitment to work and a career than their parents and grandparents

(B) less of a commitment to work and a career than their parents and grandparents

(C) a smaller commitment to work and a career than that of their parents and grandparents

(D) less of a commitment to work and a career than their parents and grandparents had

(E) a lessening of the commitment to work and a career that their parents and grandparents had

答案选D。我想问C为什么不对啊，commitment与that of their parents and grandpartents对应不是挺好么

PS：在GMAT-PREP SC语法笔记中这道题被排为18题。

C选项就好比：

I have a better notebook than yours. 有什么不妥么？

谢谢！

C

1.small我觉得多是修饰‘看得见’‘摸得着’的东西，比方说形状，面积，体积，块头，的大小；

less可以是noun或adj，所以less of没问题，less既可以修饰数量上的多少，可以强调程度上差别；

所以commitment在这里，用less修饰更好；

2.that指代commitment我觉得没问题，但是在这句里，that仍有两个弱点，

第一个，作比较时，前面说sb have sth 后面是sth of sb明显不如前后都是sb have sth好，所以不选that是对比出来的，如果没有前后have对应的选项，我觉得也可以用that of sb；

第二个，that of有与后面that形成对称的嫌疑，这个错误很牵强，我拿一个OG的例子，你看一下解释，

(B) extinction; its numbers are now five times more than

(C) extinction, their numbers now fivefold what they were

(D) extinction, now with fivefold the numbers they had

(E) extinction, now with numbers five times greater than

  官方的解释，

  Choices D and E wrongly use a phrase introduced by now with to modify The gyrfalcon.

  In both choices, the phrase confusingly seems to parallel with extinction;
                

  可见Gmat要求我们用词的时候，也要注意‘避嫌’；

谢谢，这个解释太精辟了！

没错,但凭什么用had补足而不是用did

have作为有的时候是实意动词