Question

The points having equal potential are
B and c
B and D
C and D
A and B
(diagram is in the photo)​

Answer 1

A and B have same potential because the distance from the center in both case is same.

Answer 2

First of all, always remember that equipotential surfaces for a point charge is concentric circles.

Since points A and B are present at same radii from the point charge (in the same circle), they have the same potential.

$\boxed{V_{A} =V_{B} = \dfrac{kq}{r} }$

So, point A and B have same potential !

OPTION 4) is correct .