GENERAL KNOWLEDGE

Detailed explanation-1: -The correct answer is lucite. The conventional hard contact lenses were made of a hard plastic material called polymethyl methacrylate also known as Lucite. Hence, Option 3 is correct.

Detailed explanation-2: -Contact lenses are made using the polymer Polymethyl Methacrylate which is generally known as PMMA. The lenses made using PMMA are known as hard lenses and were used commonly when first made. Now soft lenses made of polyacrylamide polymer are preferred more than hard lenses.

Detailed explanation-3: -The correct answer is Hydrogel.