Why is B wrong ?

After reading A and B , i feel postive about A , but initially i chose B .

B changes the meaning,

the sentence wants to say that "Married women" are better off.. B states otherwise!

arora007 wrote:Married women raising young children do not respond to social stresses as poorly as unmarried women do.

A) as poorly as unmarried women do.
B) as much as unmarried women do.
C) as poorly as unmarried women.
D) as much as unmarried women have.
E) as well as unmarried women.

(A) and (C) have the opposite meanings as (B), (D), and (E), yet there's no unequivocal clue in the original sentence which is the correct meaning. On the GMAT, I think you'd have to see an additional clause, so the sentence could have read like this:

"Married women raising young children do not respond to social stresses as poorly as unmarried women do; in fact, married women seem to excel in the face of social pressures when compared to unmarried women.

Now it's clear that the married women are better off (although this is an odd question, especially on a test where a great many unmarried women are infact among the test-takers...)

3. Married women raising young children do not respond to social stresses as poorly as unmarried women do.

A) as poorly as unmarried women do. - Correct
B) as much as unmarried women do. - Changes meaning.
C) as poorly as unmarried women. - Worng comparision.. Response with unmarried women
D) as much as unmarried women have. - Changes meaning
E) as well as unmarried women. - Changes meaning
IMO - A