To be honest, I'm not 100% sure on this -- it's a great example because it lets us address exactly what we should ask ourselves.prachich1987 wrote: Just one last doubt
Despite an expensive publicity campaign, ticket sales for the new play were so poor that it was closed after only two weeks
I think in above sentence IT is used correctly
It cannot logically refer to campaign,can it?
Remember (this @mundasingh, also), it's not enough to ask "Does it make sense for anything other than the play to be closed?" because, in context, of course it doesn't -- that's why common sense isn't enough. The question is: Could "campaign" be the subject, logically, of the verb "was closed"? Honestly, I think maybe it can be, so I'd be uncomfortable with the "it" and look for a choice that drops it (it always, always, always depends on the choices given on the GMAT!).
Think of it this way. What can logically "be closed"? A play, sure. A door can also be closed. A day of trading at the stock market, yes, this can be closed, too. Any of these words would present a "logical" antecedent for "it" here. How about a cocker-spaniel? This could never be the subject of the verb "to be closed," because it makes no logical sense -- so having the word "cocker-spaniel" in the sentence couldn't affect pronoun ambiguity here. I'm honestly not sure about the word "campaign" -- can you close a campaign? I think this is just on the cusp, in the blurry region of subjectivity. The GMAT shouldn't give us questions in this region, and if they do, one of two things will happen: 1) they'll give us other clues to use to make a decision (VERY often the case, so it's best to look for other issues in the sentence and in the answers before you worry about these more complex questions); or 2) Everyone will answer differently and they'll end up throwing out the question (that's why they test them experimentally first -- every question you see on test day that actually counts has already proven itself to have a "right" answer by experiment, not just by the testmaker's opinion!).
Sorry for the lack of objective answer, but, that's how English goes, sometimes












