By definition, can service-entrance cable be either single or multiconductor?

Service-entrance cable can indeed be either single or multiconductor, which makes the answer accurate. This type of cable is designed to carry electrical power from the utility service point to the service equipment in a building. As per standard wiring practices, there are configurations that utilize both single-conductor cables and multiconductor cables, depending on the specific needs of the installation, such as load requirements and distance.

Single-conductor cables are often used for specific applications where individual wires are needed, while multiconductor cables provide multiple conductors in a single cable sheath, simplifying installation and organization. Hence, recognizing that service-entrance cable encompasses both configurations aligns with the definitions and practices set forth in electrical code standards.