I thought I had to have a noun (or noun phrase) after "to"
eg) X led Y to (the production...)
Having a noun after "to", is that incorrect usage?
hanumayamma, you eliminated A) based on SVA, but can't you say that "that were increasingly unrealistic" is modifying "illustrations" (plural), rather than "the production" (singular)??
C is right
A is not wrong on the basis of SVA. Let me give you an example at hand.
The group of doctors that believe in God --> Is it the "group" or the "doctors" that believe(s) in God? In this example, it is the "doctors" rather than the "group" which believe in God.
Similarly, A can very well mean that it was the "illustrations" rather than the "production" which were unrealistic.
Usually, it is common for a restrictive clause to refer to the noun immediately preceding it.
Thus, the problem with A is simply conciseness. By introducing a clause rather than an infinitive phrase in C, it makes the sentence wordier and thus GMAT-wrong vis-a-vis C.