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Background Calculation: Line intersect X axis in -ve.
=> y = 0 => x= (-C/A)
=> for x to be negetive, (C/A) should be +ve.
So Modified Qus: whether C/A is +ve. (note question is: Are you able to answer this question.)
i) A*B -ve => either A -ve and B +ve or A +ve or B -ve A can be +ve or ve and no information about C. So Insufficient.
ii) A*C > 0 => either A and C +ve or A and C -ve. In both cases C/A is +ve. => x -ve. => Sufficient