Question

As US and Canadian cities continue to grow, they are experiencing serious problems with air pollution. Which of the following activities is not one of the most important causes of air pollution in cities?
A.

factory emissions
B.

logging and clear-cutting
C.

industrial pollution
D.

vehicle emissions

Answer 1

Answer: B. logging and clear-cutting.

Air pollution is a problem in most major cities, and this pollution has several causes. Factory and vehicle emissions are two of the most important ones, while industrial pollution also contributes significantly. Logging and clear-cutting are the least important factors out of the options, as they do not directly contribute to pollution. However, abundant trees reduce the impact of pollution on the ecosystem, so logging and clear-cutting are still to be controlled or discouraged.

Answer 2

Logging and clear-cutting