Match the ions given in Column-$I$ with their nature given in Column-$II$.

Column-$I$	Column-$II$
$A$. $CH_3-O^{+}=CH-CH_3$	$1$. Stable due to resonance
$B$. $F_3C^{+}$	$2$. Destabilised due to inductive effect
$C$. $(CH_3)_3C^{-}$	$3$. Stabilised by hyperconjugation
$D$. $CH_3-CH^{+}-CH_3$	$4$. $A$ secondary carbocation

(A-1,2; B-2; C-2; D-3,4) $A-1, 2$; $B-2$; $C-2$; $D-3, 4$
$A$. $CH_3-O^{+}=CH-CH_3$: This is an oxonium ion. It is stable due to resonance: $CH_3-\ddot{O}^{+}-CH-CH_3 \leftrightarrow CH_3-\ddot{O}=CH^{+}-CH_3$. It is also destabilised by the $-I$ effect of the oxygen atom.
$B$. $F_3C^{+}$: Destabilised due to the strong $-I$ inductive effect of three fluorine atoms,which withdraw electron density from the positively charged carbon.
$C$. $(CH_3)_3C^{-}$: Destabilised due to the $+I$ inductive effect of three methyl groups,which increase electron density on the already negatively charged carbon.
$D$. $CH_3-CH^{+}-CH_3$: This is a secondary $(2^{\circ})$ carbocation. It is stabilised by hyperconjugation from the six $\alpha$-hydrogens.