In the given LR circuit, the switch S is closed at time t = 0. Then, 

The ratio of induced emfs in the inductors of inductance L and 2L will be constant

The ratio of induced emf’s in the inductor of inductance L and 2L will be time varying

The potential difference ‘${\text{V}}_{\text{A}}{\text{- V}}_{\text{B}}$’ increases with time

The potential difference ‘ ${\text{V}}_{\text{A}}{\text{- V}}_{\text{B}}$’ will be constant.