Choose the correct statement($s$).
$(A)$ The order of basicity is $II > I > III > IV$ .
$(B)$ The magnitude of $p K_{ b }$ difference between $I$ and $II$ is more than that between $III$ and $IV$.
$(C)$ Resonance effect is more in $III$ than in $IV$.
$(D)$ Steric effect makes compound $IV$ more basic than $III$.
