各位牛牛请帮忙看看OG的一题语法解释,困惑中

请教一个问题:

OG语法49#

The cameras of the Voyager II spacecraft detected six small , previously unseen moons circling Uranus, which doubles to twelve the number of satellites now known as orbiting the distant planet.

(A) which doubles to twelve the number of satellites now known as orbiting

(B) doubling to twelve the number of satellites now known to orbit

(C) which doubles to twelve the number of satellites now known in orbit around

(D)doubling to twelve the number of satellites now known as orbiting

(E) which doubles to twelve the number of satellites now known that orbit

正确答案为B,这也是偶选的,没问题.

关键是OG后的ETS的答案分析有没看懂的地方:

Answer to Question 49
The pronoun which should be used to refer to apreviously mentioned noun, not to the idea expressed in an entire clause. In A, C, and E, which seems to refer to a vague concept involving the detection of moons, but there is no specific noun, such as detection, to which it can refer. Also in E, the use of the phrasing the number...now known that orbit is ungrammatical and unclear. B and D use the correct participial form, doubling, to modify the preceding clause, but D, like A, uses known as orbiting rather than known to orbit, aphrase that is more idiomatic in context. B, therefore, is the best answer.

这里说which不能修饰整个句子,而doubling却可以.但偶怎么觉得which在非限定性定丛时是可以修饰主句的一部分,甚至是整个主句的.所以看到这样的解释后就晕了.是不是我的理解上有问题?which到底可以修饰什么,不可以修饰什么?此题应该如何理解呢?

还请各位牛牛帮帮忙,期待ing...

谢谢leijing!

我想再问一下"which 只能只待具体的名词，不能指代整个事件"是不是只在GMAT中的规定?一般语法书上都说which可以代整个句子的.

Gmat rule, 'which' only refers to its immediate noun.

Read OG one more time.