Question 1 (Worth 4 points) Which of the following statements about the U.S. Clean Air Act is true? The Clean Air Act of 1970 focused on about 200 air pollutants. The most dramatic improvement in air quality has been a reduction in lead in the atmosphere. This is a correct answer Sulfur dioxide emissions since 1970 have been reduced by approximately 75%. The Clean Air Act was passed in 1970 and then updated in 1977 and 2005. Urban areas have done the best job of meeting the standards for clean air