Which of the Following Is an Electrical Safety Rule for Hydrotherapy

Which of the following is an electrical safety rule for hydrotherapy interventions?

A) Patients should not touch the turbine, including the on/off switch, when it is running.
B) Whirlpool turbines should only be plugged into two-prong electrical outlets.
C) Ground-fault circuit interrupters are required for large whirlpools but are unnecessary for small ones.
D) Multiple electrical devices, such as whirlpool and electrotherapy devices, can be used simultaneously on a patient provided that at least one of the devices is grounded.