请问两道题

1. A rise in co-ops being built next year should bring New York a few billion new dollars in costruction, making the building industry's health much more vibrant than a decade ago.

(A) making the building industry's health much more vibrant than a decade ago.

(B) and making the building industry's health much more vibrant than a decade ago.

(C) making the building industry's health much more vibrant than it was a decade ago.

(D) to making the building industry's health much more vibrant than a decade ago.

(E) in making the building industry's health much more vibrant than a decade ago.

正确答案是C，而我选了A，两个答案的区别是C多了it was，可我感觉A更简洁，为什么不对呢？

2. IRS provision 12Y requires that a corporation with assets greater than $500,000 send W-2 forms to their full-time employees on or before January 1.

(A) that a corporation with assets greater than $500,000 send W-2 forms to their full-time employees on or before January 1.

(B) a corporation with assets greater than $500,000 send W-2 forms to its full-time employees on or before January 1.

(C) that a corporation with assets greater than $500,000 send W-2 forms to its full-time employees on or before January 1.

(D) a corporation with assets greater than $500,000 send W-2 forms to their full-time employees on or before January 1.

(E) a corporation with assets greater than $500,000 sends W-2 forms to its full-time employees on or before January 1.

正确答案是E，而我选了B，为什么sends比send正确呢？我记得固定用法是require sb. to do sth. 但是这里没有to send 的选项，所以感觉send 也可能正确。在动词require后再出现sends怎么可能正确呢？还是一个从句？？？

望一起杀G的朋友们帮帮忙。谢谢！~

1 将c改为which makes the building industry's health much more vibrant than it was a decade ago.可能更好理解些。health 后相当于省略了that is（如A所示）,如果than后没有it was ,那么是which make...比十年前更vibrant了呢？还是industry's health 比十年前更vibrant呢？所以，没有it was 会产生歧义。

2.如果IRS provision 12Y （不知道是什么意思）是句子的主语，只有C才是唯一正确的答案。

我是说health 后相当于省略了that is，而且为了与IT WAS对应,更清楚地说明问题。

请问楼上，IT 指什么，WAS后省略了什么呢？

我认为，如果作为一个单独的比较的句子，本句应该就是

the building industry's health IS much more vibrant than it was a decade ago