Answer:
d. all of the above
Step-by-step explanation:
Particulate Matter(PM): It refers to the mixture of solid particles and liquid droplets found suspended in the air. These are microscopic particles that are too small to be seen naked eye. They are divided in two categories: PM10, having size of around 10 micrometer and PM2.5, having size of around 10 micrometer.
These are major source of pollution. Both natural and man-made activities result in the increase of particulate matter. Here all the mentioned sources are sources of particulate matter.
Automobiles use fossil fuels which is source of particulate matter.
Road dust, dust from construction sites and unpaved road also contributes and are a major contributor to city pollution as far as PM2.5 is concerned.
Forest fire, coal fire and stubble burning in farms also contribute in particulate matter concentration.
Since they have a very small size especially PM2.5, they can deposit in lungs and result in various health complications.