The correct answer is D. Melamine.
Melamine is a white, odorless, and tasteless organic compound with the chemical formula C3H6N6. It is a member of the amine family and is used in the production of a variety of products, including plastics, resins, and adhesives. Melamine is also used in the manufacture of melamine dinnerware, which is a type of plastic crockery that is known for its durability and resistance to stains and scratches.
Decron is a type of polyester that is used in the manufacture of a variety of products, including clothing, furniture, and carpets. Nylon is a type of polyamide that is used in the manufacture of a variety of products, including clothing, textiles, and ropes. Bakelite is a type of thermosetting plastic that is used in the manufacture of a variety of products, including electrical insulation, cookware, and jewelry.
Melamine is the most suitable polymer for making plastic crockery because it is durable, resistant to stains and scratches, and non-toxic.