Match the following:

List-$I$	List-$II$
$A$. Titanium	$I$. Non-metal
$B$. Fluorine	$II$. Transition metal
$C$. Tellurium	$III$. Lanthanoid
$D$. Dysprosium	$IV$. Metalloid

Observe the following statements:
$a$) The basic strength of $Lu(OH)_3$,$Gd(OH)_3$ and $Ce(OH)_3$ follows the order: $Ce(OH)_3 > Gd(OH)_3 > Lu(OH)_3$
$b$) $O^{2-}$,$N^{3-}$,$F^{-}$ and $Na^{+}$ are isoelectronic species
$c$) The sizes of $Zr$ and $Hf$ are approximately the same
The correct statements are:

Which of the following is $NOT$ a physical or chemical characteristic of interstitial compounds?

The most stable oxidation state of iron is:

The aqueous solution of which of the following ion is colourless?

Transition elements act as catalysts because....