Consider two coherent point sources (S1 and S2) separated by a small distance along a vertical line and two screens P1 and P2  placed as shown in Figure. Which one of the choices represents the shapes of the interference fringes at the central regions on the screens?

For any point on screen  P1, the diagram is as shown below.We can see for point P and  P' the path difference would be same and hence they will have same intensity of light. On the  x−y plane, circumference of the circle (radius y ) will also have same intensity ( ∵same path difference). Hence the shape will be circular.For screen  P2,we will get hyperbola( from the knowledge of YDSE).Therefore, the correct answer is (A).