Which of the following acids on heating gives geometrical isomers as a product?

The circle represents the most basic atom in these molecules. Which of the following is the correct representation?

Most stable carbocation among the following is

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:

How many chiral carbons are there in Reserpine (an antipsychotic drug)?

Consider the sets $I$,$II$,and $III$. Identify the set$(s)$ which is (are) correctly matched.
$I$. $\text{Staggered ethane} > \text{eclipsed ethane} \dots \dots \dots \text{torsional strain}$.
$II$. $2, 2-\text{Dimethylbutane} > 2-\text{methylpentane} \dots \dots \dots \text{boiling point}$.
$III$. $cis-\text{but}-2-\text{ene} > trans-\text{but}-2-\text{ene} \dots \dots \dots \text{dipole moment}$.