Question

_________ became the world's largest single source of air pollution by the 1990s.
A. Auto emissions
B. Waste incineration
C. Metal smelting
D. Chemical emissions

Answer 1

Answer:

The answer is C. Auto Emissions

Explanation:

In the 1990's cars were the new thing of the time and since they were older models they didn't and couldn't properly dispose of gasoline in a gas form that polluted the air until newer versions came out that consumed less gasoline and produced less pollution.

Answer 2

During the 1990s, Auto emissions became the world's largest single source of air pollution. Learn about auto emission below.

What is Auto Emission?

Auto emission also known as automobile emission is the release of harmful substances through a vent or exhaust of automobiles such as trucks, cars, etc.

During the 1990s, statistics showed that the release of gases and smoke from automobiles was the leading cause of pollution. Auto emissions became the world's single source of air pollution.

Learn more about Auto Emission here:

https://brainly.com/question/14397977

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