Match List I with List II :

List I	List II
A. $\text{C}_2\text{H}_4$	I. $3\ \sigma$ bonds, $2\ \pi$ bonds
B. $\text{C}_2\text{H}_2$	II. $3\ \sigma$ bonds, one lone pair
C. $\text{CH}_4$	III. $4\ \sigma$ bonds
D. $\text{NH}_3$	IV. $5\ \sigma$ bonds, $1\ \pi$ bond

Choose the correct answer from the options given below :

For $\text{C}_2\text{H}_4$ (Ethene), the structure is $\text{H}_2\text{C}=\text{CH}_2$. It contains $4$ $\text{C}-\text{H}$ single bonds and $1$ $\text{C}=\text{C}$ double bond. A single bond is a $\sigma$ bond, and a double bond consists of $1$ $\sigma$ and $1$ $\pi$ bond. Total bonds: $5\ \sigma$ bonds and $1\ \pi$ bond. Thus, A matches IV.

For $\text{C}_2\text{H}_2$ (Ethyne), the structure is $\text{HC}\equiv\text{CH}$. It contains $2$ $\text{C}-\text{H}$ single bonds and $1$ $\text{C}\equiv\text{C}$ triple bond. A triple bond consists of $1$ $\sigma$ and $2$ $\pi$ bonds. Total bonds: $3\ \sigma$ bonds and $2\ \pi$ bonds. Thus, B matches I.

For $\text{CH}_4$ (Methane), the central carbon atom is bonded to $4$ hydrogen atoms via single bonds. Total bonds: $4\ \sigma$ bonds. Thus, C matches III.

For $\text{NH}_3$ (Ammonia), the central nitrogen atom is bonded to $3$ hydrogen atoms via single bonds and has $1$ lone pair of electrons. Total bonds: $3\ \sigma$ bonds and one lone pair. Thus, D matches II.

The correct matching is A-IV, B-I, C-III, D-II.

Answer: A-IV, B-I, C-III, D-II