The underlined portion is a parenthetical element, which is indeed a hypothetical subjunctive ; It actually means- If a number of these debts be repudiated – The text is a kind literary form of writing, just as we write, Had I not seen him, rather than, If I had not seen him. However, the real issue is that it is just an addendum to the core of the sentence. The actual subject of the clause in question is - the solvency - (of some of the world’s …) this is singular and the verb therefore is required to be singular, namely, -is-.

We have A and E using the right verb –is- and E falls by, because of wrongly using the future tense for the conditional clause.
Of course, there are also other errors in B, C, and D.
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243. Developing nations in various parts of the world have amassed $700 billion in debts; at stake, should a significant number of these debts be repudiated, is the solvency of some of the world’s largest multinational banks.
(A) should a significant number of these debts be repudiated, is
(B) should a significant number of these debts be repudiated, are
(C) should they repudiate a significant number of these debts, are
(D) if there is a repudiation of a significant number of these debts, would be
(E) if a significant number of these debts will be repudiated, is

Answer is A...
My Explanation:
First take - are Vs is....
Are is wrong as we are talking about the solvency of the multinational banks.... and this is singular...
Consider this... to understand this better.....
at stake [strike], should a significant number of these debts be repudiated,[/strike]is the solvency of some of the world’s largest multinational banks

Hence we have A , D, E left....
Second take - if Vs should
If is wrong here as we need to have 'then' with it... the idiom is If X then Y.. and not If X , Y... or If X, would be Y

Hence A is a clear winner!

A is the correct answer.

The first part of the sentence, before the semicolon can be eliminated, as it is not part of the subject.

The subject is 'solvency' and the verb is 'is'.

Now, referring to the technique in MGPREP SC Guidebook, if the verb precedes the subject (in this case, 'is' precedes 'solvency'), then FLIP the structure of the sentence to get the correct answer.

FLIP IT -> the 'solvency' of some of the world's largest multinational banks 'is' at stake, should a significant number of these debts be repudiated.

Why is D out, can some one please explain

Posted from GMAT ToolKit

In present conditional sentences, the conditionals will be in present tense, while the main sentence or the effect sentence will be in either simple present or future tense. The use of 'would be' is a wrong diction in the context. Hence D is wrong
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Developing nations in various parts of the world have amassed $700 billion in debts; at stake, should a significant number of these debts be repudiated, is the solvency of some of the world’s largest multinational banks.

(A) should a significant number of these debts be repudiated, is

(B) should a significant number of these debts be repudiated, are
we need a singular "is" to go with the singular "solvency"

(C) should they repudiate a significant number of these debts, are
we need a singular "is" to go with the singular "solvency" also I'm not sure if "they" refers to the nations or the banks

(D) if there is a repudiation of a significant number of these debts, would be
the 'if' structure is inappropriately used and requires a 'then' to follow. Also "would be" renders the rest of the sentence awkward

(E) if a significant number of these debts will be repudiated, is
the "if" structure is "iffy" in this context

If i select b, there will be two simple sentence without any conjunction. Can you please make me clear about this.

Hi Priya15081, B is incorrect because of the verb "are" at the end, which should go with the singular "solvency". Answer choice A looks exactly like B except for the correct verb "is" at the end, and is therefore correct vs answer choice B.

As for answer choice E, the tense doesn't work properly either. You need the subjunctive mood as this situation has not yet occurred and is only an option at this point. Answer choice A uses the subjunctive mood (should a significant number of these debts be repudiated ). A is correct all around.

P.S. Who knew what repudiated meant? That's a fancy word!

Hope this helps
-Ron
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here the subject is solvency hence options B&C are out. in If and then clauses, below rules should be followed.
If ( Present tense), then ( simple present or simple future) - based on the context.
Future tense - will or hypothetical verbs such as would never come in if clause.
source - E gmat.

(A) should a significant number of these debts be repudiated, is
The solvency is the subject and "is' is the verb
no Sv error
(B) should a significant number of these debts be repudiated, are
SV error are is wrong
(C) should they repudiate a significant number of these debts, are
Same as B
(D) if there is a repudiation of a significant number of these debts, would be
Wrong use of conditional tense
(E) if a significant number of these debts will be repudiated, is
same As D[/quote]

only A survive
Hence A

How can answer choice 'b' be wrong.? A significant number of these debts construction is plural. I read that 'The number of' is singular.

The subject of the verb "is" is "the solvency ", which is singular. This is a case of subject-verb flip that may pose confusion sometimes. The basic structure is actually as follows:

The solvency (of some of the world’s largest multinational banks) is at stake.

sayantanc2k : Thank you for the reply. In most of the SC questions, the subject comes at the beginning, hence identifying the verb becomes easier. But in questions such as these, how to identify the subject.? Does a preposition preceding the 'noun' be defined as a subject.?

To find the subject, keep reading until an appropriate candidate comes up! Typically, the subject will be the first noun you see that isn't part of a modifier. Looking at the second independent clause (after the semicolon), here's how we might proceed:

at stake--This is a prepositional phrase. That's a modifier, so "stake" can't be the subject.

,should a significant number of these debts be repudiated,--This is a modifier. One clue is that it's set off with commas. Another is that it is serving as a qualifier. If this happens, the main action will happen, but we haven't seen what that main action is yet.

is--This is our verb, but where's the subject?

the solvency --Here's our subject! It's the first noun that is not part of a modifier.

of some of the world’s largest multinational banks.--This is a long modifying phrase. It simply adds details to the word "solvency."

So, shortening things down, the simple core of the clause is "At stake is the solvency." In more traditional order, that's "The solvency is at stake." The reversed Yoda-talk here is a turn of phrase equivalent to "What is at stake is . . . " One point of this usage (aside from making the problem harder) is to create a sense of drama: something is at stake. What is it? This construction also makes the very long modifier on the subject a bit less unwieldy by placing it at the end. Consider the two sentences below:

Not present at the meeting was my boss. There is no reason to write the sentence this way, unless I am contrasting with another, longer sentence "Present at the meeting were X, Y, and Z. Not present was my boss." As it is, it's just backwards!

Not present at the meeting were the many supporters of the plan, none of whom received invitations. Here, the subject has such a long modifier that it makes sense to move the whole thing to the end. The sentence wouldn't be wrong the other way ("The many supporters of the plan, none of whom received invitations, were not present at the meeting.") However, it may not make its point as clearly and forcefully. Also, until we get to the last word, we don't know what the invitations are referring to.

For a similar construction, take a look at this one: what-was-as-remarkable-as-the-development-of-the-compact-139154.html
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Subject in 2nd clause is "At stake" so we require "IS"

Now B/w A and E
E- not correct
as Will cannot come with If in same clause
eg . If I play , I will win.
Here Will and If need to be in different clauses so this is correct.

if a significant number of these debts will be repudiated-Wrong construction

So A is correct.

Give kudos if you like explanation

What is the exact difference between if and should?

Manhattan guide says : In case of conditional should and must .... be avoided.... Is this not contrary ?
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ShankSouljaBoi
The idea is that if we already have an "if," we don't want to use "would" or "should": "if you would" or "if you should." (This is actually common in real life, but not so much in the kind of formal grammar the GMAT uses.) In this question, "should" is used as an alternative for "if," so we don't have the redundant/confusing "If you should."
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