Scholars have been quarreling over various purported portraits of Will

D is wrong because of "igniting". Gerund makes it sound as if Stanley is doing the action. Instead, the intended meaning is that the fact he found Cobbe RESULTED into the fuss. So, S only did one action, which resulted ["ignited"] into the fuss among the dissenters.

Scholars have been quarreling over various purported portraits of William Shakespeare for years, and in 2009 the Cobbe portrait was unveiled by Stanley Wells, who claimed that it was the only authentic likeness to have been painted in Shakespeare's lifetime, ignited yet another fuss among the dissenters.

Here's how I see it,
1. Scholars have been quarreling over X
2. AND in 2009 the portrait was unveiled by Y, WHO (referring back to Y) blah blah blah IGNITED yet another fuss among Z

Potential Errors
No need to use the verb+ing form "igniting" since we don't really need to show any progressive action.
Y ignited the debate among the supporters - this must be made clear by using "who"

D & E are out, because we need to refer back to Stanley Wells from the previous clause.
B is out because it unnecessarily uses "which" and uses the -ing form.

A is incorrect because the sentence looks like "the portrait was unveiled by Stanley wells ignited" vs "the portrait was unveiled by Stanley wells who ignited", which is what C fixes

if the meaning of correct sentence is hard to understand, then of course, the incorrect meaning in incorrect choices are hard to realize and so we have a hard question.

SW ignited the fuss among few people by claiming something. We are looking for this sentence structure.

A. who claimed that it was the only authentic likeness to have been painted in Shakespeare's lifetime, ignited portrait was unveiled by SW..... ignited. This structure doesn't make sense
B. who claimed it was the only authentic likeness painted in Shakespeare's lifetime, which, igniting 'Which' is unnecessary
C. who, in claiming that it was the only authentic likeness to have been painted in Shakespeare's lifetime, ignited unveiled by SW who ignited fuss. Correct answer
D. claiming that it was the only authentic likeness painted in Shakespeare's lifetime and igniting 'claiming' and 'igniting' need not be parallel as one led to the other
E. with his claim that it was the only authentic likeness to have been painted in Shakespeare's lifetime ignited. sentence is not connected properly

GMATNinja can you explain please?

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.