If (1+a)b=b, which of the following must be true?  Choices:
A) a=-1 or b=0  B) a=0 or b=0  C) a=1 or b=1  D) a=-1 or b=-1  E) a=0 or b=1
By only having ab=0, we cannot say answer is B as A and E options also satisfy the condition ab=0. ans a=0 or b=0
<result>B</result>
If (1+a)b=b, which of the following must be true?