(A) While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity.
(C) Even though it costs about the same to run nuclear plants as for other types of power plants, it is the fixed costs that stem from building nuclear plants that makes the electricity they generate more expensive.

it is fixed costs (that stem from building nuclear plants) (that makes the electricity they generate)
That makes the electricity they generate is modifier FOR BUILDING NUCLEAR PLANTS, is not it?
If that were not present then it would have modified fixed costs.

Please clarify on this as experts have pointed S-V disagreement. I am not clear on this .
AndrewN EMPOWERgmatVerbal AjiteshArun

Hi mSKR,

Let's start by taking a look at that it, but in a different (shorter) sentence:

1. The corruption scandal torpedoed his career. ← This is fine.

2. It was the corruption scandal that torpedoed his career. ← This is the same sentence, but the way it is constructed draws extra attention to the corruption scandal. This could be used (for example) to emphasize that it was the corruption scandal (and nothing else) that "torpedoed his career".

We can read (2) like this:

3. The corruption scandal was the thing that torpedoed his career. ← Notice how we're still talking about the corruption scandal. The scandal was what "torpedoed his career".

Now, back to what we see in this question:

4. It is the fixed costs that stem from building nuclear plants that makes {something} more expensive. ← This sentence uses the dummy it that we see in (2). The makes is a problem, because the fixed costs is what the that-clause (that makes...) refers to.

To see why the that in that makes refers to the fixed costs, let's try to remove the it at the beginning of the sentence (like going from (2) to (1)):

5. The fixed costs that stem from building nuclear plants make {something} more expensive. ← We must switch from the singular makes to the plural make, as the subject (the fixed costs...) is plural.

So, it is not building nuclear plants that makes something more expensive. It is the fixed costs that make {the electricity the nuclear plants generate} more expensive.

As for your second question, we cannot remove the second that:

6. It is the fixed costs that stem from building nuclear plants makes {something} more expensive. ← The verb makes is left hanging here. It is not connected to anything in the sentence.
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I guess than in b one have to assume than the ellipsis looks like?:
(B) While the cost of running nuclear plants is about the same as the cost for running other types of power plants, the fixed costs that stem from building nuclear plants make the electricity they generate more expensive.

If the answer if affirmative why not use the preposition "of" instead of "for"?

It is absolutely right to use 2 modifiers to the same noun without using AND as I can learn from this question?
Do I not need to use AND?


It is the fixed costs ..
...that stem from building nuclear plants
...that makes the electricity xx

It is fixed costs that stem from building nuclear plants and that makes the electricity xx
or
It is fixed costs , stem from building nuclear plants , that makes the electricity xx


Is this concept similar to the concept explained here:
https://gmatclub.com/forum/sartre-an-in ... l#p2722237 GMATGuruNY
https://gmatclub.com/forum/sartre-an-in ... l#p2722235 AndrewN

Please suggest AjiteshArun AndrewN @GMATGuruNY

Hi mSKR,

That's a great question! The two situations are not the same. A simple way to think about this particular situation is that the two relatives (the that-clauses) that we see here aren't really the same.

1. X is Y. ← Absolutely straightforward!

2. It is X that is Y. ← "Repackaged" version of (1). This that-clause is just a way to (for example) add emphasis.

Now the problem we face in this question is that there is a that-clause inside the X as well.

3. It is the fixed costs that stem from {something} that make {something} more expensive.

The point to note here is that the two that-clauses are not exactly the same. That is, we cannot say this:

4. It is the fixed costs that stem from {something} and that make {something} more expensive.

The whole the fixed costs that stem from {something} is one unit. In other words, the sentence is:

5. It is [the fixed costs that stem from {something}] that make {something} more expensive. ← "It is [X] that is Y."

To see this, let's try to remove that dummy it:

6. The fixed costs that stem from {something} make {something} more expensive.

Do you see how the that stem... bit stays as it is and continues to describe the fixed costs but the other that-clause is no longer there in the sentence? That's because that particular that-clause was never really meant to describe the fixed costs at all, not in the same way as the first that-clause. It was a way to "repackage" that sentence.

At the end of the day, what we're saying is that the "repackaged" version of "X is Y" could be "it is X that is Y" but not "it is X and that is Y". We can't add an and there just because the X has a that-clause in it.
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This is one of the questions which is not in normal form. So it is better to deal with new structure ( if we are not aware) to make it in simple form and check if this sentence makes sense. If the sentence makes sense then consider logic more important and check for other errors as in A.

So our approach to reject A and acceot B should be:


(A) While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity.

Hints to reject A and give priority B:
for them extra words: B doesn't have these words - is there any better choice?
It: pronoun insertion : B doesn't have extra pronoun. - is there any better choice?
consider structure: if makes modifies building nuclear plants then 2nd part of sentence left is : it is the fixed costs that xx that yy - must be wrong or else unknown structure also has similar structure
Finally, what makes expensive to generate electricity? Building nuclear plants can make expensive , how? if cost associated in building is considered, so makes should refer to fixed costs logic wise.


How would be your approach if you come across a not-normal structure first time?
Consider logic first?

Please share your thoughts. AjiteshArun AndrewN

Thanks!

Hello, imSKR. I agree with AjiteshArun in those two thorough posts to your queries above. I would like to point out that these that clauses in question are both referring back to fixed costs, but not in the same capacity. The first goes into the origin of the costs and relies on a prepositional phrase, never resolving the main clause in any meaningful way, while the second completes the original thought with a verb in the embedded clause, to make, that introduces the object of the clause, the electricity. It is a subtle issue, but the comma or and marking the two clauses as parallel entities should not be present. We could stack that clauses one after another, without commas or using and, as long as the information we were getting was subordinate to some series of nouns. Consider a rambling (non-GMAT™) sentence in which we encountered three such clauses before we popped back into the main clause:

It is the fixed costs that stem from building nuclear power plants that are supposedly friendly to an environment that is burdened with pollution that comes mostly from human activity that make the electricity that such plants generate more expensive.

Again, such a tangential sentence would not appear as an answer choice on the GMAT™, certainly not as a correct answer. The point, though, is that that clauses can be added without and or the use of commas in certain circumstances. In the original sentence, the first that clause would not create a meaningful, non-dialogue-based sentence on its own, while the second would, so the two entities are not the same. To illustrate:

1) It is the fixed costs that stem from building nuclear power plants. (Unfinished thought. Fixed costs stem from building nuclear plants? Do fixed costs not stem from building other types of power plants or anything else? Why is the emphasis on fixed costs in particular? What are these costs doing, or what effect do they have?)

2) It is the fixed costs that make the electricity [more expensive]. (Complete thought with an effect.)

If we were to add a second effect in that form, within such a clause, we would indeed use a comma or and:

3) It is the fixed costs that make the electricity more expensive, that eventually cause people to complain when they see their energy bills.

Notice that either that clause would complete the thought of the sentence on its own. I have already illustrated this notion with sentence 2 above, but consider the second half on its own:

4) It is the fixed costs that eventually cause people to complain when they see their energy bills.

The issue is one of meaning more than one of grammar. You can study the example of this question and its variant sentences, but I doubt you will find the same issue crop up too often, if at all, in other questions.

I hope that helps. Thank you for thinking to ask me.

- Andrew

GMATNinja
Thank you sir for the broad explanation. Everything makes sense to me other than the highlighted part!
From the sentence it seems that the subject for the verb makes is building nuclear plants NOT 'the fixed costs' both in choice A and C.

Only in this choice, the subject for the verb make is the the fixed costs
Sir, am I missing anything? Could you clarify, please?
Thanks__

The subject-verb issues in (A) and (C) are discussed in detail here and here. Let us know if those don't clear up your question.

Also, please be aware that we receive literally hundreds of questions every month on the forums -- far more than we could dream of answering in detail -- and you'll receive better responses from forum experts if you pick your battles carefully. I'd recommend asking for a specific expert's help only when you're sure that your question hasn't been answered elsewhere on the thread -- and I'd also recommend keeping your overall volume of expert reply requests in mind.

I hope that helps a bit!
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