Alternating Current (AC) is commonly used because it:

Alternating Current (AC) is preferred primarily because it can be transmitted over longer distances with less loss compared to Direct Current (DC). This advantage stems from the way AC voltage can be easily transformed using transformers, allowing for adjustments to higher voltages for long-distance transmission. Higher voltages reduce the current for the same power level, which, in turn, decreases the I²R losses (where I is current and R is resistance). Therefore, when AC is used, it's possible to efficiently transmit electrical energy over vast distances, which is crucial for connecting power generation sites (such as power plants) to consumers. This capability is one of the foundational reasons why AC has become the standard for electricity distribution in many regions around the world.

Other options provided do not accurately capture the primary advantages of AC in transmission systems, especially regarding efficiency and loss reduction in long-distance applications. Understanding these principles is essential for grasping why AC is widely utilized in modern electrical systems.