Question

which process is a source of outdoor air pollution?
releasing mold particles from an air conditioning vent
emitting particles from a dump truck
releasing radon gas from a generator
emitting carbon monoxide from a heater

Explanation:

• Mold particles from an AC vent are an indoor pollution source.
• Radon from a generator and carbon monoxide from a heater are also indoor air pollution sources.
• A dump truck operating outdoors emits particulate matter directly into outdoor air, making it an outdoor air pollution source.

Answer:

emitting particles from a dump truck