Correct option is D zero and min.
When the dipole is in the direction of field then net force is $\mathrm{q} \mathrm{E}+(-\mathrm{q} \mathrm{E})=0$ and its potential energy is minimum $=-$ p.E $=-\mathrm{qaE}$
Correct option is D zero and min.
When the dipole is in the direction of field then net force is $\mathrm{q} \mathrm{E}+(-\mathrm{q} \mathrm{E})=0$ and its potential energy is minimum $=-$ p.E $=-\mathrm{qaE}$