If (y - 1)(z - 3) + 5(y - 1) = 0, then which of the following must be true?  Choose the correct answer.
A) y = -4 and z = -3
B) y = 4 or z = -3
C) y = -4 or z = 3
D) y = 1 and z = 3
E) y = -1 or z = 3
factor out:   (y-1)(z-3+5)=0   (y-1) (z+2) = 0   So by checking options we get ,   Ans - y = 1 and z = 3
<result>D</result>
If (y - 1)(z - 3) + 5(y - 1) = 0, then which of the following must be true?