Airborne mercury has received special attention because it is a widespread and persistent neurotoxin(a substance that damages the brain and nervous system). Minute doses can cause nerve damage and other impairments, especially in young children and developing fetuses. The majority of airborne mercury is released by __________.
A. Metal ore smelting
B. Coal-burning power plants
C. Waste combustion
D. Nuclear Power plants
E. Wood-burning power plants