请教PREP01-142,比较句谓语省略问题！

hoteldeville

142.
According to a 1996 study published in the Journal of Human Resources, Americans of Middle
Eastern descent were twice as likely as was the national average to be self-employed.

(A) as was the national average to be self-employed
(B) as the average American to be self-employed
(C) as the national average that they would be self-employed
(D) to be self-employed than was the average American
(E) that they would be self-employed than was the national average

解析：
(A) the national average表达不清楚；was可以省略。
(B)正确，the average American与Americans of …对称，be likely to do。
(C) the national average表达不清楚；be likely that…的正确表达方式是用it作形式主语it+be likely
that…，而不是sth be likely that…；they指代对象不清楚。
(D) as… than搭配错误。
(E) as… than搭配错误；be likely that…的正确表达方式是用it作形式主语it+be likely that…，而不是
sth be likely that…；was可以省略。

可是我觉得B也不好。不知道为什么可以省略was啊？前者的谓语是复数were，后者是单数was，当单复数不同时，不是不可以省略吗？

justinlee17

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