Question

Before the 1980s, gasoline combustion was a major source of which environmental pollutant?

a) Carbon dioxide (CO₂)
b) Sulfur dioxide (SO₂)
c) Nitrogen oxides (NO₂)
d) Particulate matter

Answer 1

Before the 1980s, gasoline combustion was a major source of lead (Pb) pollution.

Step-by-step explanation:

Before the 1980s, gasoline combustion was a major source of lead (Pb). As a result of regulatory efforts to remove lead from gasoline, emissions of lead from the transportation sector dramatically declined by 95 percent between 1980 and 1999, and levels of lead in the air decreased by 94 percent during that time period.