Q:Q: What are the two main types of air pollutants? Read this paragraph and choose the correct option from the provided answers: There are two main types of air pollutants: primary and secondary. Most air pollutants come from burning fossil fuels. Some come from burning forests. Some are due to the evaporation of chemicals. Choices: - a and b - new and old - good and bad - primary and secondary A:
A:
primary and secondary