What is the product of the reaction between ${\text{C}}_6{\text{H}}_5{\text{N}}_2^{+}{\text{Cl}}^{-}$ and ${\text{C}}_6{\text{H}}_5\text{OH}$ in a basic medium?

Solution

1. The diazonium cation acts as an electrophile in an electrophilic aromatic substitution reaction.
2. Phenol is activated by the $-\text{OH}$ group, which directs the electrophile to the ortho and para positions.
3. Due to steric hindrance, the para product is the major product.
4. The resulting compound is $\text{p-hydroxyazobenzene}$.
5. Hence the answer is (A).