Is particulate matter a primary or secondary pollutant?

Particulate matter is present in both categories of atmospheric pollutants. Primary pollutants are substances directly emitted from a process, such as; ash from a volcano, or carbon monoxide gas from a vehicles exaust.

Secondary pollutants are pollutants that are formed by the combination and reaction of primary pollutants and other substances, smog is a good example.

the answer is d.) homologous; have mammary glands

my teacher would say no s