If ab=0, is |a-b|>0?
1) a=0
2) b<0
==> If you modify the original condition and the question, you get is a≠b? Also, there are 2 variables (a, b) and 1 equation (ab=0), in order to match the number of variables to the number of equations, there must be 1 equation as well, and therefore D is most likely to be the answer.
For con 1), you get a=b=0 no a=0 and b=3, hence yes, it is not sufficient.
For con 2), you get b<0 and a=0, hence yes, it is sufficient. Therefore, the answer is
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1) a=0
2) b<0
==> If you modify the original condition and the question, you get is a≠b? Also, there are 2 variables (a, b) and 1 equation (ab=0), in order to match the number of variables to the number of equations, there must be 1 equation as well, and therefore D is most likely to be the answer.
For con 1), you get a=b=0 no a=0 and b=3, hence yes, it is not sufficient.
For con 2), you get b<0 and a=0, hence yes, it is sufficient. Therefore, the answer is
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