If the system of linear equations
x−2y+kz=1
2x+y+z=2
3x−y−kz=3

has a solution (x,y,z),z≠=0, then (x.y) lies on the straight line whose equation is :
A. 3x−4y−1=0
B. 4x−3y−4=0
C. 4x−3y−1=0
D. 3x−4y−4=0