IFC Is a Unique Form of Electrical Stimulation in That

IFC is a unique form of electrical stimulation in that it deals with what is referred to as a "third line" of current. Which of the following statements most accurately reflects the potential benefit of a "third line" of current?

A) The third line is a created field within the body, which can be potentially stronger than either of the individual intensities of the channels.
B) The third line is a created field within the patient, which can be either stationary or made to move to decrease polarization of the sensation.
C) There is no such thing as a "third line" with IFC; this is a marketing term.
D) The third line is another name for pre-modulated IFC, meaning that only one channel is necessary to elicit the desired response.