Historians believe that, for most countries involved in the conflict

Intuitively we suspect option A and test maker in this question capitalized that tendency.

The crucial part is non-underlined portion - "though many still point to the assassination of Archduke Franz Ferdinand as ..." which demands for more active and direct clause in introductory clause. Thus "Historians believe that" is more preferable than "The historians' belief is".

Secondly, prepositional phrase " for most countries involved in the conflict" should be placed closer to its related part [World War I's root causes were varied] for better logical clarity. Here, starting with that prepositional phrase made the construction bit clumsy.

Hope it works.

this question use the simple structure of sentence to test logic. in other words, all of us have enough grammar knowledge to solve this question but still many persons are wrong

because they do not use meaing analysis

for most countries involved, the historian believed

the is no logic relation between main clause and for-phrase.

Im not an expert but here's my 2 cents-

One straight reason to eliminate D:
D) For most countries involved in the conflict, the historians' belief that World War I's root causes were varied and complex

Since its belief and not believe, a verb is missing for the subject historians. And hence without a valid subject-verb pair, there is no main clause int his sentence.

A bit of theory if you would like-
A correct sentence always contains at least one main clause. A main clause, in turn MUST have at least one valid subject-verb pair. In the given sentence, historians-believe is the valid pair. Changing believe to belief (as done in option D) removes the only verb for historians in the sentence.
The second part of the sentence (starting with though) is a subordinate clause that needs a main clause to depend upon.

So, you see, just a small change of verb to noun has created chaos in the sentence

Hope that helps

Strainght A - Logical and without any grammatical errors

Hi,

This is a logic test.


A) Historians believe that-believe what?

, For Whom-for most countries involved in the conflict,

World War I's root causes were varied and complex-the thing that historians believe

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Pls correct me if I am wrong, but i was always under the impression that (,) should not be used with That?
Which is why I eliminated A.
Is it not the case?

Great question! The comma isn't there because of the word "that" is it there because we need two commas to set aside the non-essential info that follows:

Historians believe that, for most countries involved in the conflict, World War I's root causes were varied and complex, though many still point to the assassination of Archduke Franz Ferdinand as the immediate precursor to war.

So it is in modifier and hence we ignore it, Thanks

(A) Historians believe that, for most countries involved in the conflict, World War I's root causes were varied and complex
Believe - correctly used for historians
For most countries - correctly modifies "believe"
Were - correct as per "causes"
No errors in this choice

(B) Historians believe that variation and complexity were there for most countries involved in the conflict by the World War I's root causes
"involved in the conflict by the WWI's root causes" - changes the meaning of the sentence. Provides a meaning that the countries were there in the war because of these causes - wrong

(C) The historians' belief is, for most countries involved in the conflict, root causes were varied and complex for World War I
Cannot find any grammatical/meaning flaw in this. Option A is just simpler

(D) For most countries involved in the conflict, the historians' belief that World War I's root causes were varied and complex
Here belief - is not a verb.
were - verb for causes
belief - does not have a verb

(E) For most countries being involved in the conflict, historians believe that the root causes that World War I had were varied and complex
"Believe that root causes that WWI has ..." - can be expressed in much simpler form as expressed in option A

Correct - Option A

Historians believe that, for most countries involved in the conflict, World War I's root causes were varied and complex, though many still point to the assassination of Archduke Franz Ferdinand as the immediate precursor to war.

(A) Historians believe that, for most countries involved in the conflict, World War I's root causes were varied and complex - Correct

(B) Historians believe that variation and complexity were there for most countries involved in the conflict by the World War I's root causes -- changes the meaning.

(C) The historians' belief is, for most countries involved in the conflict, root causes were varied and complex for World War I -- not concise/not as good as A

(D) For most countries involved in the conflict, the historians' belief that World War I's root causes were varied and complex -- not concise/not as good as A

(E) For most countries being involved in the conflict, historians believe that the root causes that World War I had were varied and complex-- not concise/not as good as A

GMATNinja, GMATNinjaTwo, generis

Here I feel E is right since in A, the essential part 'for most countries involved in the conflict' is within comma, making it a non-essential. without that the sentence reads
" Historians believe that World War I's root causes were varied and complex".
E although awkward still conveys the intended meaning
Kindly assist.

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