A forest fire is considered a short-term environmental change because it occurs quickly and its effects can be seen immediately. While other options like ice ages and mountain building represent long-term geological processes, forest fires cause temporary ecological disturbances. Recovery from such events can happen over months to a few years, illustrating the transient nature of this change. ;
A forest fire is considered a short-term environmental change because it occurs quickly and its effects are immediately visible. Other options, such as ice ages and mountain building, represent long-term processes that unfold over extended periods. Therefore, the correct answer is A. forest fire.
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