What are the two types of plastic?

• A. They are a type of metal.
• B. They are naturally occurring only.
• C. Naturally occurring and man-made.
• D. They are not plastics.

Answer: (C)

Plastics are polymers, and they come from two origins: naturally occurring polymers found in nature and man-made (synthetic) polymers produced in industry. Naturally occurring plastics include materials like natural rubber and shellac, while most modern plastics are synthetic, made by polymerizing monomers from fossil fuels or renewable sources. So the idea being tested is recognizing that plastics can be sourced from either nature or human-made processes. The other statements don’t fit because plastics aren’t metals, and plastics aren’t limited to one origin—their polymers can be natural or synthetic.