From the following, how many compounds contain at least one secondary alcohol? Choose the correct answer from the options given below:

Step-by-step solution

A secondary alcohol has the OH group on a carbon bonded to exactly two other carbon atoms. Analyzing each structure: I contains only primary alcohols and carboxylic acid. II has OH on a carbon bonded to two other carbons (secondary alcohol). III has tertiary and primary alcohols only. IV has secondary alcohols on the cyclopentanone ring. V has OH on a secondary carbon (between two CH groups). VI has the central carbon as tertiary with three OH groups. Compounds II, IV, and V contain at least one secondary alcohol,