The correct option is B (2,0)
Focus of the parabola is S≡(0,0)
and x=4 is the directrix.
we know that axis of the parabola is perpendicular to the directrix and pass through the focus of the parabola.
∴ intersection of directrix and axis of the parabola is (4,0)
Also, vertex of parabola is the mid point of its focus and foot of directrix.
Hence, required vertex =(2,0)