If xy+5z = x(y+z), which of the following must be true?	Choose the most appropriate option:
A) 1. x=0 and z=0
B) 2. x=5 and z=0
C) 3. y=1 and z=0
D) 4. x=1 or y=0
E) 5. x=1 or z=0
xy+5z=x(y+z)   xy+5z=xy+xz   5z=xz   it means x=5 or z=0   Answer 2. x=5 and z=0
<result>B</result>
If xy+5z = x(y+z), which of the following must be true?