The invention of the elevator in the mid-nineteenth century was significant not only for the convenience it represented, also it ushered in a new era in architecture, allowing buildings to become increasingly tall.
This is from MGMAT SC question bank.
I nailed the right answer but I am still not happy. I think "it" is kind of ambiguous and does not clearly refer to elevator(which is the intention!). The correct answer choice also has "it" but I guess it is correct as it is the "best" option, right? Thanks!
Pronoun ambiguity is something with which you have to tread very carefully. We are finding that pronoun ambiguity is not something you should put a lot of stock in. As long as you could eliminate the other answers for legitimate reasons you can feel comfortable with the "it".