请教大全第10题

benelaine

10。A large rise in the number of housing starts in the coming year should boost new construction dollars by several billion dollars, making the construction industry’s economic health much more robust than five years ago.
(A) making the construction industry’s economic health much more robust than five years ago
(B) and make the construction industry’s economic health much more robust than five years ago
(C) making the construction industry’s economic health much more robust than it was five years ago
(D) to make the construction industry’s economic health much more robust than five years ago
(E) in making the construction industry’s economic health much more robust than it as five years ago
请问。C助动词补出was根据何在。
        我的理解是it指making the construction industry’s economic health；
        补全的话为...than making the construction industry’s economic health was robust five years ago.
        可是前面的动词是making阿
请解释

lizaz

it 指 economic health

zhouhaichen

为什么要补出 it was ? 前面并没有economic health 并没有is 啊.
顶一下.