Final answer:
The excerpt 'O holes in the ozone' expresses an opinion on ozone depletion.
Explanation:
The excerpt "O holes in the ozone" expresses an opinion as it reflects the author's concern and perspective on the issue of ozone depletion. In contrast, the statement "I wonder if they will even exist for my children" is a contemplation but not an opinion as it presents a pondering thought.
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https://brainly.com/question/1996171
