Alcohols are the compounds containing hydroxyl group attached to the alkyl group, whereas phenols are hydroxyl derivatives of aromatic hydrocarbons in which hydroxyl group is directly attached to carbon atom of aromatic ring. Alcohols are versatile compounds and can behave both as nucleophiles as well as electrophiles.
Phenols, too are reactive compounds and are known to undergo reactions on : phenolic group, benzene ring as well as various other name reactions like Reimer-Tiemann reaction, Kolbe's reaction etc.

The major product of the given set is:

The correct answer is option 3.

The reaction will be as follows:

The reaction above is Kolbe's reaction. Kolbe’s reaction, also known as Kolbe Schmitt Reaction, is a type of addition reaction named after Hermann Kolbe and Rudolf Schmitt. When phenol is treated with sodium hydroxide, phenoxide ion is generated. The phenoxide ion generated is more reactive than phenol towards electrophilic aromatic substitution reaction. Hence, it undergoes an electrophilic substitution reaction with carbon dioxide, which is a weak electrophile. ortho-hydroxybenzoic acid (salicylic acid) is formed as the primary product. This reaction is popularly known as Kolbe’s reaction.

Mechanism

Kolbe’s reaction can be classified as a carboxylation chemical reaction. The reaction occurs when sodium phenoxide is allowed to absorb carbon dioxide, and the resulting product is heated at a temperature of a 400 K and a pressure of 4-7 atm. An unstable intermediate is now formed.

This unstable intermediate goes through a proton shift, leading to the formation of sodium salicylate. Now, this mixture is treated with sulfuric acid. The acidification of the mixture yields salicylic acid.