In multiwire branch circuits, the continuity of the _____ conductor shall not be dependent upon the device connections.
a) ungrounded
b) grounded
c) grounding electrode
d) a and b
See answer and applicable Code reference
The correct answer is: b) grounded
General wiring method requirements are outlined in Art. 300 of the 2011 NEC. Mechanical and electrical continuity rules for conductors are noted in Sec. 300.13. As specifically noted in 300.13(B), "In multiwire branch circuits, the continuity of a grounded conductor shall not depend on device connections such as lampholders, receptacles, and so forth, where the removal of such devices would interrupt the continuity."