The correct option is
A AFor the given situations of charges,
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1097739/original_2.png)
Here,
F32>F31
⇒→Fnet=→F32−→F31
(towards the equilibrium position
)
Therefore, it is a stable equilibrium.
For
A:
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1097765/original_8.png)
When the ball is displaced from its equilibrium position, it will try to come at its original position.
Thus, it is in stable equilibrium.
For
B:
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1097767/original_9.png)
When the ball is displaced from its equilibrium position, it will never come back to its original position.
Thus, it is in an unstable equilibrium.
For
C:
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1097769/original_10.png)
When the ball is displaced from its equilibrium position, it has no tendency to go anywhere.
Thus, it is in neutral equilibrium.
Hence, option
(A) is correct.