State an important advantage of using AC over DC

AC voltage can be easily transformed to higher or lower values, making long-distance power transmission efficient and less costly.

Alternating current changes direction periodically. This allows simple transformers to step up voltage for transmission and step it down for safe domestic use. High voltage reduces current for the same power, which cuts I²R losses in wires.

As a result, AC grids move power over hundreds of kilometers with manageable losses. AC machines like induction motors are robust and widely used. While modern HVDC links exist for specific cases, AC remains the backbone of public power systems because of transformer compatibility and easy distribution.