What Is Automatic Vehicle Location (AVL)

What is automatic vehicle location (AVL) ?

A) Uses GPS tracking to track vehicles
B) Uses plastic or conductive polymers instead of silicon-based microchips,allowing them to be washed or exposed to water without damaging the chip
C) A device that measures the acceleration (the rate of change of velocity) of an item and is used to track truck speeds or taxi cab speeds
D) A satellite-based navigation system providing extremely accurate position,time,and speed information