Which of the following is NOT a type of circuit used for street lighting?

Street lighting typically utilizes various circuit configurations to ensure efficient operation and reliability. The common types of circuits used include multiple circuits, parallel circuits, and series circuits.

In a parallel circuit, multiple light fixtures are connected across the same voltage source. This configuration allows each fixture to operate independently; if one light goes out, the others remain lit, which is ideal for street lighting as it ensures continued illumination even if one light fails.

In a series circuit, all light fixtures are connected in a single path. If one fixture fails, the entire circuit is interrupted, causing all lights to go out. While series circuits can be less expensive to install, they are generally not suitable for street lighting due to the potential for complete failure if one light burns out.

Multiple circuits refer to configurations that use more than one circuit line to distribute electricity to various sections, providing flexibility and reliability in operation.

On the other hand, the term "complex" does not specifically refer to a standardized circuit type used in street lighting systems. It can imply a variety of configurations or setups but does not represent a commonly recognized or practical configuration for street lighting purposes. Therefore, it is the option that is not typically associated with the operational standards and practices for street lighting circuits.