yes, "those" refers to "set designs" - both logically and structurally (noun, including that/those for something specific...) - you'd expect that/those to refer to the noun before including.
So, here's something weird. I recognize this question; it's from my company. But the question as typed above does not match our question in the database. I'm guessing that it has "mutated" as people have posted it in random places around the web. Be very careful about where you get the material you study. If something has been passed around enough, inadvertent changes are made and that can sometimes mess up the problem.
In this case, there are changes, but the right answer is still in there (though it's a different letter / position). Though there is still a problem... read on.
We've got a split at the beginning: including vs. like. "Including" indicates something that actually belongs to whatever category is being discussed. "Like" indicates something that is only similar to whatever is being discussed. Which is it here? We're not just talking about designs "similar to" the 1942 film. We're actually talking about those designs. So eliminate B and C.
We've also got a singular / plural pronoun split: those vs. that. The antecedent (set designS) is plural, so eliminate B and D, which use the singular "that."
Here's where I'm not thrilled with whoever swapped things around here. At some point, someone swapped answers A and E. A and E are almost identical, except that A uses present tense and E uses future. In the original question (as we wrote it), the "will" future tense was given in the original sentence (and choice A). We can easily argue that the phrase "future generations" indicates that we should use future tense. But you could have an unusual construction that uses present tense here - and if that present tense is shown in choice A, the original sentence, then we should accept the intention of the author. The real test wouldn't make us make this kind of choice - which is why this question, as officially written, placed the "will" in the original sentence (and, therefore, answer choice A).
Bottom line: try to study right from the source. When you pick stuff up off of the web, even seemingly minor changes can make a difference in the validity of the material and what you are learning when you study it. Whoever swapped the two choices either didn't notice or thought for some reason that it wouldn't matter to make such a minor change. But it actually does matter, to some extent, in this case.
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Stacey Koprince
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Manhattan GMAT
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