Although the earliest records we have of Arabic sources using the

Question

Although the earliest records we have of Arabic sources using the number zero date back to 773 C.E.,  the fact that the Arabic civilization had been performing advanced mathematical operations for a century before that indicates that  they understood the concept of numerical zero long before they ever put it in writing. After all, Indians and Babylonians had both developed the concept independently before then, and the Arabic people could reasonably be expected to have acquired similar concepts.  And although there is a dearth of writing indicating the exchange, by the 6th century C.E. Arabs had been in close contact with Indian civilization for a prolonged period .

In the argument given, the two portions in boldface play which of the following roles?

(A) Both bolded sections are evidence that seem to contradict the author's argument.

(B) The first is a summary of the position the author seeks to promote; the second is a dismissal of that position.

(C) The first is a methodological basis for findings examined in the argument; the second is an explanation of that methodology.

(D) Both bolded portions are pieces of evidence that potentially support a position promoted by the argument.

(E) The first is a piece of evidence supporting the author's conclusion; the second is that conclusion.

Source: Ready4Gmat
 The passage's point seems to be that the Arabic people had the idea of zero before the numeral was developed. It states that the Arabic people had been performing advanced calculations for a century before the numeral was developed; that other cultures had developed the idea before then; and that they could have acquired the idea through interaction with India. These all seem to be evidence for the passage's point. 
Choice (A) is not correct, because the boldfaced portions support the argument, not contradict it. 
Choice (B) is incorrect because the second boldfaced portion does not reject the author's position. 
Choice (C) is incorrect because the passage doesn't mention any "methodology." 
Choice (D) looks good, because the boldfaced portions do imply support for the idea that the Arab civilization had the concept of zero before the numeral; the first boldfaced portion indicates how advanced the Arab people were mathematically, and the second suggests they could have gotten the idea from India. 
Choice (E) is incorrect because the second boldfaced portion is not a "conclusion." The conclusion is more accurately said to be in the last part of the first sentence: "  understood the concept of numerical zero long before   ever put it in writing."
The correct answer is Choice (D).

Abhishek009 · Answer

THe highlighted part of the stimulus is the main conclusion of the Arguement....

Check what does the 2 Bold parts doe -

B1 : Supports and Provides additional information that coerces the reader in believing the authors argument by providing information about the mathematical knowledge..
B2 : Supports the idea that Arabs knew the concept of zero though there was a dearth of writing at that time...

Thus, both the bold parts provides evidence in buying the authors argument, Answer must be (D)

ArupRS · Answer

Conclusion - " they understood the concept of numerical zero long before they ever put it in writing"

Both the bold part actually supports this conclusion. Hence D.

VerbalBot · Answer

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Although the earliest records we have of Arabic sources using the

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