Hint: Nucleophilic substitution reaction: A strong nucleophile replaces a weak nucleophile.

Explanation:

(1) The first reaction is an example of an electrophilic aromatic substitution. In this reaction, the electrophile Cl⁺ attacks the benzene ring and substitutes the hydrogen atom.

(2) In the second reaction, the addition of HBr takes place on to the doubly bonded carbons of Propene in accordance with Markownikoffs rule and electrophilic addition takes place.

(3) In the third reaction, the reactant is a secondary halide. Here, the halogen atom is substituted by hydroxy ion, As it is a secondary benzyl halide so it follows S_N¹  mechanism.

(4) In the fourth reaction, the halogen atom is directly bonded to the aromatic ring. So, It is a nucleophilic aromatic substitution reaction, as the -OH group has substituted halogen of a given compound.

Hence, option 1 is the correct answer.