The excerpt showcases the man's blunt realization of his vulnerability in the unforgiving Arctic environment.
The selected sentence that demonstrates a blunt portrayal of natural life in the excerpt from Jack London's "To Build a Fire" is: 'He chuckled at his foolishness, and as he chuckled he noted the numbness creeping into the exposed fingers.'
In this sentence, the man's reaction to his situation in the harsh Arctic environment reflects a stark portrayal of how nature's conditions directly impact survival.
The text vividly illustrates the man's struggle with the extreme cold and his realization of his vulnerable position in the unforgiving natural setting.
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