Godot Community

Hi!
I need to make an object selection system. As I understand it, it can be implemented via RayCast2D - I change RayCast2D.Position to the mouse position and objects are detected. But the problem is this: In my game, some objects are one under the other and GetCollider() returns two objects. I need only the topmost object to be selected, and the one below it is not selected. How to implement it?