Multiple Choice
The "ozone hole" is caused by the:
A) buildup of toxic ozone in the troposphere over cities such as Los Angeles from human-caused pollution.
B) depletion of ozone in the troposphere by chemicals such as CFCs.
C) depletion of ozone in the stratosphere by chemicals such as CFCs.
D) increase in warming due to high levels of ozone in the troposphere.
E) depletion of ozone in the troposphere due to greenhouse gases.
Correct Answer:

Verified
Correct Answer:
Verified
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