Electric field intensity at a point varies as $\frac{1}{r^3}$ due to:

a short electric dipole

The correct answer is Option (2) → a short electric dipole

$E_{axial}=\frac{1}{4πε_0}.\frac{2Pr^3}{r^3}$

$E_{equitorial}=\frac{1}{4πε_0}.\frac{Pr^3}{r^3}$

∴ Electric field intensity at a point varies as $\frac{1}{r^3}$ due to a short electric dipole.