I was asked privately to take on these questions, so even though there are already explanations elsewhere, I'll do it!
1. Public-access cable television was created in the 1970s as a means to derive public benefit from the laying of private television cables on public land.
A) from the laying of private television cables on public land
ANSWER: Nothing wrong so far as I can see.
B) from laying private television cables on the public land
PROBLEM: I'm not sure there's any problem with removing the article before "laying" ("the"). This is a gerund either way (For example: "THE running of the bulls is a crazy fun event." OR: "Running with the bulls is crazy fun.") However, putting "the" in front of public land makes it sound specific ("the" is a definite pronoun, which always makes things sound specific), as opposed to general public land, which is what we want to describe.
C) by the laying of private television cables on the public's land
PROBLEM: Idiom should be "benefit from" not "benefit by". Make "public" possessive is a bit logically weird, if not grammatically incorrect.
D) from private television cables being laid on public land
PROBLEM: We always hate "being". This is a terrible construction when we could just choose the gerund form in A/B.
E) by laying private television cables on land that was public
PROBLEM: Idiom. And what the heck is that "was public" about?
2. The guiding principles of the tax plan released by the Treasury Department could have even a greater significance for the economy than the particulars of the plan.
(A) even a greater significance for the economy than
PROBLEM: Idiomatically, we can only put the word "even" before a word without an article, not the other way around. I can say "an even better mousetrap", but I can't say "even a better mousetrap".
(B) a significance that is even greater for the economy than
PROBLEM: This is a comparison question, so we need to work out the two things we want to compare. In this case it's "the guiding principles" (having a greater significance) than "the particulars". The problem is that without the "do" we get in D, there are two possible readings of this sentence. Either the significance of the principles is greater than for the economy than the particulars are greater for the economy (the meaning we want), or the significance of the principles is greater for the economy than the particulars (of something...in general).
It's a long version of "I play with Dave better than John." In that sentence, it could be that I play better with Dave than I do with John, or that I play with Dave better than John plays with Dave. Whenever there are two possible readings, you need to add something to clarify.
(C) even greater significance for the economy than have
PROBLEM: A weird parallel thing happens here. The first "have" is part of a conditional ("With more money, I could have everything I want."). But this second have sounds like the past perfect tense ("Those principles have had a lot of significance"). This represents a change in tense that we don't want.
(D) even greater significance for the economy than do
ANSWER: Gets the comparison right (adding the word "do").
(E) a significance even greater for the economy than have
PROBLEM: Comparison is wrong here. Sounds like greater for the economy than for something else. Also, the "have" is still wrong.
Hope that helps!
Tommy Wallach | Manhattan GMAT Instructor | San Francisco
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