Each direct-buried single conductor cable must be located _____ in the trench to the other single conductor cables in the same parallel set of conductors, including equipment grounding conductors.
a) perpendicular
b) bundled together
c) in close proximity
d) spaced apart
See answer and applicable Code reference
The correct answer is: c) in close proximity
Section 300.5 of the 2011 NEC covers the wiring methods for underground installations. As noted in 300.5(I), "All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors shall be installed in the same raceway or cable or shall be installed in close proximity in the same trench."
