Given: Polymer ' X ' is mainly used for making unbreakable cups and laminated sheets. We're asked: What are the monomers of polymer X ? Step 1: Identify the polymer Unbreakable cups and laminated sheets are typically made from melamine-formaldehyde or phenol-formaldehyde type resins. However, phenol-formaldehyde resin (commonly known as Bakelite) is specifically known for: Being hard and brittle Used in electrical switches, unbreakable crockery, laminated sheets, etc. Step 2: Match with monomers Bakelite (phenol-formaldehyde resin) is formed by: Phenol + Formaldehyde → Phenol-formaldehyde resin (Bakelite) Hence, the monomers are phenol and formaldehyde. Correct Answer: Option C: phenol and formaldehyde