Which system of equations represent the matrix shown below?
1 2 -1| 8
-1 0 3| 15
1 -2 4| 18
A. x + 2y + z =8
x + y + 3z =15
x + 2y + 4z =18
B. x + 2y + z =8
x + 3z =15
x + 2y + 4z =18
C. x + 2y - z =8
-x + y + 3z =15
x - 2y + 4z =18
D. x + 2y - z =8
-x + 3z =15
x - 2y + 4z =18