for the first time in five years california authorities have issued a first stage smog alert, warning people in some areas of unhealthy levels of ozone in the air. smog contains several dangerous chemical compounds beside ozone: sulfur dioxide, nitrogen dioxide, and carbon monoxide. since it would be impossible to wear gas masks like those in the picture, a reasonable plan would be to
a) stay indoors as much as possible to limit exposure during the alert.
b) wear cotton surgical masks outside to prevent exposure.
c) move to another state to avoid exposure.
d) distribute portable oxygen masks to all citizens.