Consider two identical charges placed a distance `2 d` apart on the `x`-axis.The equilibrium of a positive test charge placed at the point `O` midway between them may be
(i) neutral
(ii) stable for displacement along the `x`-axis
(iii) stable for displacement along the `y`-axis
(iv) unstable for displacement along the `x`-axis

Options

A. `(i),(ii),(iii)`
B. `(i),(iii) ,(iv)`
C. `(i),(ii),(iv)`
D. `(ii),(iii),(iv)`

Answer

4

Explanation

Identical charges may be `+ve` or `-ve`.