The equation of x-axis is of the form
x=0
y=0
x+y=0
x=y
The points on the x-axis are of the form (a,0), where a is any real number.
The y-coordinate of the point of thex-axis is 0.
Thex-axis is represented by the equation y=0
The equation of x-axis is y=0
Hence, option (B) is correct.