Hey Imskpwr,
I know you're gonna kill me, but I'll continue to recommend you post entire questions when asking stuff here. And here are the reasons:
1) The GMAT tests your ability to work out the best choice among a number of options. Often, there is no perfect answer choice. So trying to isolate problems without anything to compare them to is questionable.
2) Posting a full question allows everyone to see how good a question it is (people post from a lot of weird, not very good sources here on the forums), and thus whether the issues raised by it are likely to show up on the real test in the same format.
3) GMAT questions test multiple subjects in the splits, but often only if you see all the answer choices.
Okay. All that being said, we can look at this:
1) Generally, we would want to say "costs the same amount of something." It's weird/informal to use the word "same" when we don't technically know what it's the same as.
2) Major pronoun craziness here. There are three manifestations of the expletive "it". This very ugly/messy.
3) Subject-verb agreement: "makes" has "fixed costs" as the subject, which is plural. The sentence should say "make".
4) Meaning issue. As written, the sentence is kinda illogical. It's not the fixed costs of building that make it more expensive for nuclear plants to generate electricity (generating electricity is a running costs, not a fixed one). It's the fixed costs of building that make a nuclear plant less cost effective in general. Again, this is an issue that the correct answer would most likely fix in one way or another, but it's impossible to say for sure without seeing other answer choices.
5) The relative pronoun "that" could be placed better. At present, it could be modifying the "Costs" (as we want it to) or the "plants" (which it happens to touch). As with (4), the GMAT occasionally uses relative pronouns to modify compound subjects like this, but a correct answer would very likely fix it in some way.
Hope that helps!
-t
Tommy Wallach, Company Expert
ManhattanGMAT
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