In "Exhalation," the narrator realizes that devastating changes are imminent when beings no longer need to replace their air canisters regularly. This alteration indicates a significant disruption in their life-sustaining process, foreshadowing a crisis. Other options considered do not directly connect to environmental changes like option C does. ;
In "Exhalation," the narrator recognizes that significant changes are coming when beings no longer need to regularly replace their air canisters, which disrupts their life processes. This event indicates a profound alteration in their environment, suggesting that imminent crises are approaching. Therefore, the correct answer choice is C.
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