Whenever you see a pronoun split (for example: some answers have "it", others have "they), you need to ask yourself a few questions to quickly narrow down the answers:
1. Does the pronoun have an antecedent in the sentence? To check, try to replace the pronoun with another word in the sentence that you think might be the antecedent. For example:
"Bill is six feet tall, so he is a great basketball player." --> Here, you could replace "he" with "Bill" and the sentence would make sense. Bill is the antecedent of "he."
"Bill's hands are huge, so he is a great basketball player." --> Here, you can NOT replace "he" with "Bill" because the subject of the sentence is not "Bill." Instead, the subject is "Bill's hands." You cannot logically say "Bill's hands is a great basketball player," so this would be a pronoun error.
2. Is the antecedent clear and unambiguous? Essentially, you want to know whether there is more than one subject that could replace the pronoun. If there is more than one, you have a pronoun problem:
"Bill and Ted were walking to the mall, but then he got a call from his father and had to go home." --> We don't know whether "he" is referring to Bill or Ted, so this is no good.
The last note to make here is that "it" always refers to singular inanimate objects (chairs, tables, houses, corporations) and "they" always refers to plural objects, animate or inanimate (monkeys, books, etc.)
I know this is a little more general than the question you asked, but since a link to the answer was already posted I thought I'd sum up here. Good luck!
Brett Beach-Kimball | Manhattan GMAT Instructor
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