What type of circuit has equal voltage drop across all components?

The correct answer highlights a key characteristic of parallel circuits, where each component is connected across the same two common points, resulting in each component experiencing the same voltage drop. This means that in a parallel configuration, regardless of the resistance of individual components, they all receive the full source voltage.

In contrast, series circuits divide the total voltage among all components, meaning each component will have a different voltage drop based on its resistance relative to the total resistance in the circuit. Complex circuits and combined circuits may incorporate elements of both series and parallel configurations, but they do not define a characteristic where all components have an equal voltage drop.