The differential equation of the family of circles with fixed radius 5 units and centre on the line y=2 is
A. `(y-10)^2((dy)/(dx))^2+y^2 + 20y =0`
B. `(y-10)^2((dy)/(dx))^2-y^2 + 20y =0`
C. `(y-10)^2((dy)/(dx))^2+y^2 - 20y =0`
D. `(y-10)^2((dy)/(dx))^2-y^2 - 20y =0`
