Select the molecule which has only one $\pi$-bond.

The number of sigma $(\sigma)$ and pi $(\pi)$ bonds present in benzene respectively are:

Which of the following contains $p\pi - p\pi$ bonding?

$A$ molecule $(X)$ has $(i)$ four sigma bonds formed by the overlap of $sp^2$ and $s$ orbitals,(ii) one sigma bond formed by $sp^2$ and $sp^2$ orbitals,and (iii) one $\pi$ bond formed by $p_z$ and $p_z$ orbitals. Which of the following is $X$?

Number of $\sigma$ (sigma) and $\pi$ (pi) bonds in aspirin are respectively . . . . . . .