Global warming:

A. has not yet been observed.
B. has been caused by increasing levels of carbon dioxide in the atmosphere.
C. has led to a depletion of the ozone layer in the atmosphere.
D. has no serious consequences.



Answer :

Final answer:

Global warming is the increase in Earth's temperature caused by rising greenhouse gases like carbon dioxide from fossil fuel burning, with potential severe consequences.


Explanation:

Global warming is the observed increase in the Earth's temperature due to rising concentrations of greenhouse gases like carbon dioxide. The burning of fossil fuels contributes to this process, leading to warmer temperatures on Earth's surface and potential consequences such as the melting of polar ice caps and increased sea levels.


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