The states of Jammu Kashmir, Himachal Pradesh, Uttarakhand and Bihar are prone to earthquakes. What are the factors responsible for it?

I. The Himalayas have not yet attained isostatic equilibrium.

II. Himalayas are tremendously huge landmass having great height.

III. Himalayas are seismically stable land mass.

IV. Pushing of Indian Plate in the north-east direction.