Final answer:
a) Electricity. Electricity is always seeking the path of least resistance to ground, flowing through paths in the human body that have minimum resistance in a direct path to Earth. Wearing insulating shoes can help prevent current flow through the body.
Step-by-step explanation:
Electricity is always trying to seek the path of least resistance to ground. This is because larger currents preferentially flow through sections with lower resistance. In the human body, electric currents flow through paths that have a minimum resistance in a direct path to Earth, which acts as a natural electron sink. Wearing insulating shoes provides a large resistance and prohibits a pathway for electrons to flow.