The equation of the circle which bisects the circumference of the circles x²+y²=1,x²+y²−2x=3 and x²+y²+2y=3 is
A x²+y²−4x+4y−1=0
B x²+y²+2x+2y−1=0
C x²+y²+2x−2y−1=0
D x²+y²−2x+4y−1=0