Regarding Counterirritation, Which of the Following Statements Is FALSE

Multiple Choice

Regarding counterirritation, which of the following statements is FALSE?

A) The lock-and-key theory helps explain counterirritation.
B) Applying mild electric currents to the skin can alleviate pain or reduce more agonizing pain.
C) For more extreme pain, an electric current is applied directly to the spinal cord.
D) If you pinch yourself while you are having a tooth filled, you are using counterirritation.