Which of the following about improvements in air quality is correct?

Question

Quizplus · Accepted Answer

Sulfur dioxide emissions have significantly decreased due to regulations requiring power plants to reduce their emissions, which were a major cause of acid rain. Catalytic converters, mentioned in option A, are indeed used to reduce harmful emissions, but they primarily target pollutants like carbon monoxide, hydrocarbons, and nitrogen oxides, not lead. Lead emissions decreased due to the phasing out of leaded gasoline. Carbon monoxide's reduction is more directly attributed to improvements in vehicle emissions standards and technology, rather than its destruction by oxygen. Lastly, ozone levels, particularly ground-level ozone (a component of smog), are influenced by various factors including emissions of volatile organic compounds and nitrogen oxides, not by the amount of nitrogen gas in the atmosphere.

Which of the Following About Improvements in Air Quality Is