Question

If your friend asked, "Why are plastics good insulators?" you would reply:

Answer 1

I would read Choice #2 to him, enunciating clearly.

Answer 2

Explanation:

Insulators are materials that do no allow the flow of electric current inside it. The difference between conductors and insulators is that conductors have free electrons while insulators do not have. Plastic is a good insulator.

This is because materials like plastics do not have any loosely bound electrons in their outer shell making it difficult, if not impossible, for electrons to move between atoms.  

Hence, the correct option is (2).