What it means when Co-efficient of coupling between two coils of self inductances $L_1$ and $L_2$ is unity.

Two different coils have self inductance $L_1=8 \mathrm{mH}$ and $L_2=2 \mathrm{mH}$, respectively. The current in one coil is increased at a constant rate and the current in the second coil is also increased at the same constant rate. At a certain instant of time, the power given to the two coils is same. At that time, the current, the induced voltage and the energy stored in the first coil are $i_1, V_1$ and $W_1$, respectively. The corresponding values for the second coil, at the same instant, are $i_2, V_2$ and $W_2$, respectively. Now, select the incorrect option.