新pre SC-181 请教

181.
            (27438-!-item-!-188;#058&002362)

The number of people flying first class on domestic flights rose sharply in 1990, doubling the increase of the previous year. 

A. doubling the increase of

B. doubling that of the increase in

C. double as much as the increase of

D. twice as many as the increase in

E. twice as many as the increase of

我选B，答案是A，但总觉得有点问题。doubling对应的比较对象是The number of people 和the increase，两者不对等啊。

请大家帮助。

还是不太明白，如何辨别呢？请指教

明白了，逻辑上伴随前句的结果，谢谢你啊