@peco. Original sentence has two phrase separated by comma. However , this is the only sentence gives a clear contradiction and its explaination.
Option B is passive.

Expert please comment

in my opinion, using brevity, i feel option B is more conscise and way process of elimination, option A was eliminated as the correct idiom should be "as ....... as". option A uses only "as ......." . Besides, in my opinion option B equally shows the comparison intended by the sentence.

Please i need serious clarification here.....what am i assuming wrongly.

B is a faulty construction. The sentence says: "although a and b...can influence x". The sentence should continue with something that clarifies the weighting between a and b and whatever else influences x. Option A does so by saying that the influence of management decision is equal to or bigger than the influence of a and b.

B just mentions a great influence, which makes the "although-construction" awkward and unnecessary. It practically takes away part of the intended meaning of the sentence.

The "missing one as" issue is not a big one here. It can easily be left out since it's obvious what is being compared. The sentence could have ended with "as do the two formerly mentioned factors", but that really would break the flow.

Thanks for that explanation. Id try to adopt that reasoning for subsequent challenges.

jaymw wrote:B is a faulty construction. The sentence says: "although a and b...can influence x". The sentence should continue with something that clarifies the weighting between a and b and whatever else influences x. Option A does so by saying that the influence of management decision is equal to or bigger than the influence of a and b.

B just mentions a great influence, which makes the "although-construction" awkward and unnecessary. It practically takes away part of the intended meaning of the sentence.

The "missing one as" issue is not a big one here. It can easily be left out since it's obvious what is being compared. The sentence could have ended with "as do the two formerly mentioned factors", but that really would break the flow.

In a narrative context, where perhaps we may just have heard a source minimizing the role of management decisions, choice B would be ok, because the contrast would be stronger. Lacking that context, as you say, it puts the "although" in an awkward position.

Also, management decisions is less wordy than decisions of management, though English is not as tolerant as other languages are of modifying nouns with other nouns.