Pick out the $WRONG$ statements about magnetic substances ($\chi = \text{magnetic susceptibility}$, $\mu_r = \text{relative permeability}$).
$I$. Substances with $-1 \le \chi < 0$ are diamagnetic
$II$. Substances with $\chi \gg 1$ are paramagnetic
$III$. Substances with $\chi \ll 1$ are ferromagnetic
$IV$. Substances with $\mu_r \gg 1$ are ferromagnetic

• A
  $I$ and $II$
• B
  $III$ and $IV$
• C
  $II$ and $III$
• D
  $II$ and $IV$