Hi, guys

The correct idiom is "so X as to Y" - so, unfortunately, A is not the right answer. C is the only answer that does not present a grammatical error. I am curious as to the source of the question, though, because "In the Renaissance" is incorrect - it should say "During the Renaissance" but this is not even part of the underline.

Be really careful when studying questions that are not OG or from a highly reputable source - especially SC. Actually - don't be careful - just don't do it. Poorly written questions will just mess you up.

Anyway, A is wrong b/c idiom is incorrect.
B you would need to say "they were willing to ignore..."; also "to such an extent that" is wordier than "so X as to Y"
C is right
D incorrect idiom (so X that Y)
E incorrect idiom (as X as to Y)

So, they used to seem to prefer "so X as to Y" but "so X that" and "so that" are perfectly viable candidates. We're updating this in our next version of the SC strategy guide.

Strangely, in the current OG11, the explanation for one problem claims that "so X as to Y" is an INcorrect idiom... but then another problem later in the same book says the correct answer properly uses the "so X as to Y" idiom!

The only difference we could see in usage was that the incorrect problem used a clause for X while the correct problem used an adjective for X. So... beware "so X as to Y" where X is a clause.

Back to this problem. It's not an official problem. (You can tell because, among other things, "were" is the first word in all five answer choices. Official problems never do that - there's at least one change, however small, at the beginning and end of the underline.) So don't use it - if whoever wrote it can't even be bothered to follow the most basic rules for constructing an SC question, then it's not a good study problem.