C-01-Q157mediumsingle_mcqThe equation of a circle with centre (p,q)(p, q)(p,q) and radius rrr is:ax2+y2=r2x^2 + y^2 = r^2x2+y2=r2b(x−p)2+(y−q)2=r2(x - p)^2 + (y - q)^2 = r^2(x−p)2+(y−q)2c(x+p)2+(y+q)2=r2(x + p)^2 + (y + q)^2 = r^2(x+p)2+(y+q)2dx2+y2=0x^2 + y^2 = 0x2+y2=0