As a business owner, Brenda knows the importance of electrical safety. Each evening, she is the last person to leave work. Before she leaves, she makes sure that all electrical appliances are shut off and unplugged. What, if anything, has Brenda done wrong?

a. Brenda has done nothing wrong.
b. Brenda should not clean the appliances while they are plugged in.
c. Brenda should leave all appliance cords out in the middle of the floor so that people can see them.
d. Brenda should unplug the appliances by the cord, not the plug.