The term "riser" is used to identify:

• A. A vertical section of cable
• B. Transition from overhead to underground
• C. A type of fuse
• D. A cross-arm support

Answer: (B)

The term riser identifies the point where the system changes its medium from overhead to underground. It marks the transition where an underground feeder is brought up to the surface and connected to the overhead distribution, or vice versa, often at a pole or transition vault. This concept is about how the wiring path shifts from buried conductors to exposed lines, requiring appropriate transition equipment and insulation for the different installation methods. It’s not just a vertical piece of cable by itself, and it isn’t a fuse or a cross-arm support, which serve different functions in the system.