"Because land based wells require more digging,..."

[Ann T]

Hi guys, would appreciate your comment on this quiz:

Disclaimer: This is not a Gmat-format question, just a drill question in E-gmat course- SC session of pronoun. I post it on here because the "right" answer choice contradicts with what I have in mind about pronoun.

Because land based wells require more digging, calculations for estimating the amount of oil in an oil well do not apply as well to them as they do to deep sea wells.

The correct answer, by e-gmat, is A: "them" refers to "land based wells" and "they" refers to "calculations". But I have thought that both "them" and "they" must refer to only one noun in the sentence, don't they?

There are 3 other choices but they all have obvious pronoun errors (e.g. replacing them with it). I would expect something like "them as the calculations do to deep sea wells", or "land based wells as the calculations do to deep sea wells", but they were not among answer choices. So I didn't have any better answer but am still unconvinced with A as the right one.

Thank you,

[tim]

just because you have what you think is a better option in mind doesn't mean that the given option is wrong. remember, you're only looking for the best among the five choices you are presented with..

the parallel nature of the comparison here requires "they" to refer to "calculations". "them" must refer to "land based wells" because the only plural nouns in the sentence are "land based wells", "calculations", and "deep sea wells". "calculations" doesn't work because if we wanted to refer to "calculations" we would have to use "themselves" due to the reflexive nature of that thought. "deep sea wells" doesn't work because it makes no sense to compare deep sea wells to deep sea wells..

[Ann T]

Thanks, Tim. I totally agree that "them" refers to "land based wells" and "they" refers to "calculations".

What has confused me, however, is that "them" and "they" refer to different antecedents.

Chapter 12 (advanced strategy of pronouns & modifiers) in Manhattan book of SC, (page 233), rule no. 3 reads: "Repeated pronouns are presumed to refer to the same antecedent. That is, every it and its in the sentence should generally mean the same thing".

Am I misinterpreting the rule?

[tim]

the rule says "generally"; this is a case where the pronouns don't refer to the same thing..