$A$ compound was synthesized by a student,but its structure was not identified. However,his instructor told him that it was a meso compound with $5$ carbons and $2$ stereogenic centers. Which of the following structures should the student consider as possibilities for his compound?

Which of the following structures is not meso-$2,3$-butanediol?

Match List-$I$ with List-$II$.

List-$I$ (Pair of Compounds)	List-$II$ (Type of Isomers)
$A$. $2-$Methylpropene and but$-1-$ene	$I$. Stereoisomers
$B$. $Cis-$but$-2-$ene and $trans-$but$-2-$ene	$II$. Position isomers
$C$. $2-$Butanol and diethyl ether	$III$. Chain isomers
$D$. But$-1-$ene and but$-2-$ene	$IV$. Functional group isomers

Choose the correct answer from the options given below:

Which carbocation is the most stabilized?

Match the following:

$A$. Acetaldehyde,vinyl alcohol	$1$. Enantiomers
$B$. Eclipsed and staggered ethane	$2$. Tautomers
$C$. $(+)2$-butanol,$(-)2$-butanol	$3$. Chain isomers
$D$. Methyl-$n$-propylamine and diethylamine	$4$. Conformational isomers
	$5$. Metamers

Identify the correct sequence for True and False.
$(I)$ Only compounds with chiral centers can be optically active.
$(II)$ Absence of elements of symmetry is the reason for a molecule's optical activity.
$(III)$ All organic compounds contain carbon $\&$ hydrogen.
$(IV)$ Different canonical forms of a molecule represent the actual structures of a molecule which has resonance in it.