Answer:
A. [tex](x-5)^2+(y-1)^2=0[/tex]
Step-by-step explanation:
When the radius of a circle is zero, then it is called a degenerate circle.
The general equation of circle with center at [tex](h,k)[/tex] and radius of r is,
[tex](x-h)^2+(y-k)^2=r^2[/tex]
So the radius is 0, so the equation will be in form of,
[tex](x-h)^2+(y-k)^2=0[/tex]
Out of the given option A has is a circle with radius of 0.
[tex](x-5)^2+(y-1)^2=0^2[/tex]
