Is it this question? I think the hardest question in the world is the one you just asked! Am I right?
The answer is Class A. The GFCI (Ground Fault Circuit Interrupter) will “sense” the difference in the
amount of electricity flowing into the circuit to that flowing out, even in
amounts of current as small as 4 or 5 milliamps. The GFCI reacts
quickly (less than one-tenth of a second) to trip or shut off the circuit.
<span>It is a Compound machine.</span>
Make sure you but no copyright, author, and date of publication, that may help.