chlorofluorocarbons are complex, abundant, and ______. \nanthropogenic\nnaturally-formed\nessential\nunsteady

Brief Explanations:

Chlorofluorocarbons (CFCs) are man - made (anthropogenic) compounds. They are not naturally - formed as they are synthetically produced. They are not essential (in fact, they are harmful to the ozone layer) and the term “unsteady” is not an appropriate description for their nature in this context. So the correct option is “anthropogenic”.

Answer:

A. anthropogenic