which process led to the release of large amounts of carbon dioxide at the end of the devonian period?
a. the breakup of pangaea
b. the extinction of plant life
c. the melting of glaciers
d. the volcanic activity

The volcanic activity led to the release of large amounts of carbon dioxide at the end of the Devonian period

Explanation:

Devonian period is refereed as the Age of fish. It is also called an era of mass Extinction. During the end of Devonian period most of the terrestrial animals were extinct from Earth. Another big feature of Devonian period was massive volcanic activity which contributed to the release of carbon dioxide in the environment.    

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