[求助]新Prep2-222（汗...这个题号....）

In 1914 a total of 469,000 cars and trucks were produced in the United States, but in 1929 almost twice the numbers of trucks alone came off the assembly lines.

A. the numbers of trucks alone

B. that number of trucks alone

C. the number of trucks by themselves

D. as many trucks themselves

E. as many trucks by themselves

首先要确定came的主语，不能是数字吧，AC全排除

我的疑问是：

1.alone =by themselves 在这里都可以表示“仅仅卡车自己”的意思么？

2.DE前半段这样的结构是否正确？？

可以看做：as many trucks (as the cars and trucks) by themselves 的省略么？如果可以，为什么E不对呢？

万分纠结中，热切盼望各位指点！

噢噢。。。谁帮我解释一下呀~明天就考了....

难道这是传说中的2^4?

简直2到极限啦。。