The two best means of avoiding electrical shock or injury when working with power tools are?

The two recognized most effective ways to prevent electrical shock or injury when working with power tools (eg. during electrical equipment operations) are INSULATING and GROUNDING.
 
Insulating can be done by placing a non-conductive material such as plastic around the conductor, while Grounding can be done by using a direct connection to a known ground such as a metal, cold water pipe.

Your answer should be c