Question

which of the following is one of the four most dangerous indoor air pollutants as identified by the epa?
oxygen
radon gas
perfumes
carbon dioxide

Explanation:

The EPA (Environmental Protection Agency) has identified radon gas as one of the four most dangerous indoor air - pollutants. Oxygen is a necessary gas for life, not a pollutant. Perfumes can be an irritant but are not among the top - four most dangerous according to the EPA. Carbon dioxide is a natural gas and at normal indoor levels is not one of the most dangerous pollutants as identified by the EPA.

Answer:

radon gas