Although They Are Not Directly Toxic to Living Organisms,chlorofluorocarbons (CFCs)have

question 47

Multiple Choice

Although they are not directly toxic to living organisms,chlorofluorocarbons (CFCs) have had unanticipated effects on Earth's atmosphere.The ecological impacts of CFCs will be

• A) relatively benign, because even as secondary pollutants their toxicity remains low.
• B) limited to the terrestrial ecosystem only.
• C) limited to high-altitude communities where ultraviolet radiation is more intense.
• D) uniformly serious, affecting almost all ecosystems and trophic levels.

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Definitions:

Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring, a key mechanism of evolution.

Mutation

A permanent alteration in the DNA sequence that makes up a gene, varying from a single base pair to large sections of a chromosome.

Scale of Nature

A historical concept proposing a hierarchical order of living organisms from simplest to most complex, often associated with pre-Darwinian theories of evolution.

Aristotle

An ancient Greek philosopher and polymath, whose extensive writings cover diverse subjects including physics, biology, metaphysics, logic, ethics, and politics, significantly influencing Western intellectual history.