A time varying voltage `V=2t` volt is applied across an ideal inductor of inductance `L=2H` as shown in figure. Then select incorrect statement
Options:
(a) current versus time graph is a parabola .
(b) energy stored in magnetic field at `t = 2 s is 4J`
(c) potential energy at time `t=1` s in magnetic field is increasing at a rate of `1 J'/'s`
(d) energy stored in magnetic field is zero all the time