SC700-800 一道关于which和Ving修饰的题

几许VV

Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A） was an underground remnant of Earth's earliest days, sporadically erupting
C） was an underground remnant of Earth's earliest days, which sporadically erupted

给的答案是A，我选的是C

解释里说的是：A的sporadically erupting正确指代了an underground remnant of Earth's earliest days；C的which错误指代了Earth's earliest days

我的疑问：
1. 逗号+Ving放在句末做后置定语修饰前面名词是非常不优的结构，因为看起来像伴随修饰Geologists once thought这个动作，OG里也有相应的考点
2. 退一万步说，就算逗号+Ving可以做后置定语修饰an underground remnant，那两个选项都是an underground remnant of XXX，凭什么A就正确修饰了remnant，C就错误修饰了XXX？

LZ这么看下来，觉得这一题C是更好的选择，因为1.避免了Ving伴随状语的歧义 2.这里which跨介词修饰意思非常清楚，修饰remnant完全没问题
希望有大神可以发表意见，一起讨论，先谢谢了！

邹森森森蝶

赞！！！！

几许VV

刚刚去搜了一下，发现Ron男神居然和我想的一样啊啊啊啊啊啊啊啊好激动啊啊啊啊

放在这里给大家参考！

以下内容来自GMATCLUB

I knew that A is wrong... only C makes some sense.. wasted 2 hours in refreshing all concepts of ing modifer and relative clause modifying distant noun, gmatclub thread and following thread. Finally, I am happy because I can rely on my knowledge.

Ron said:::
https://www.manhattanprep.com/gmat/forums/geologists-once-thought-that-the-molten-rock-known-as-lava-t722-45.html

We are retiring this problem in its current form, because it has several issues.

First, as you point out, "which" is not necessarily wrong here.

Second -- and more importantly -- the ostensibly correct answer to this problem doesn't actually work.
In choice A, the modifier "sporadically erupting..." does not describe anything in the preceding part, so it doesn't make sense as a "comma + __ing" modifier (which must meaningfully describe the subject+action of the preceding sentence).
Incidentally, choice A of the Dickinson problem (OG12 #26) is wrong for exactly the same reason!

This problem is no longer in our database. It will be replaced by an updated (and fully correct) version soon.

Because the problem is no longer in the database, this thread is now retired.

Thanks.