关于OG11-9的一点思考

Saixss

Sunspots, vortices of gas associated with strong electromagnetic activity, are visible as dark spots on the surface of the Sun but have never been sighted on the Sun's poles or equator.
(A)    are visible as dark spots on the surface of the Sun but have never been sighted on
(B)    are visible as dark spots that never have been sighted on the surface of the Sun
(C)    appear on the surface of the Sun as dark spots although never sighted at
(D)    appear as dark spots on the surface of the Sun, although never having been sighted at
(E)    appear as dark spots on the Sun's surface, which have never been sighted on

对于C选项，我想问，它的错误原因是不是因为ALTHOUGH在这里引导的是状语从句，本应修饰的是前面APPEAR的主语sunsports，但又由于前面没有逗号，所以又需要去修饰与它最近的词dark spots从而造成了修饰上的模糊不清呢？？
希望大NN指点！！！谢~~~

verylotus

这是OG的解释：although/though是从属连词（不是并列连词），通常要引导完整的主谓结构句子
可是我看到过好多although不补全的例子。。如Negative feedback by another person, although unpleasant, can be justified in certain circumstances.
诡异了，难道是在GMAT里一定要补全吗？困惑，想请斑斑解答一下。。。顶。。。。

Jungle_cheng

这句话的句意，可以看出中心是要体现“sunspots却从来没有出现在sun‘s poles”。
如果是C选项的话，你的句意就将中心完全转移了。
我认为，Although是可以不用补全，但是其引导的句子，句意中心是在后半句上，类似于有点递进的从属关系。
所以我认为A相对而言，更好，更符合句意。

Jungle_cheng

而且，我觉得，C中，Although后面是否应该加have never been，因为Although的主句谓语是are，而从句这里应该用have been，所以从句不能省略谓语。
只有当主从句，主谓语都一致，才能够省略。