Concept:The poem reflects a serious, reflective attitude toward ageing and life choices.Explanation:The speaker in The Panic of Growing Older confronts the realities of adulthood with seriousness.He moves into a quiet domestic life and then examines whether his past years were meaningful.This tone is thoughtful and restrained, not proud, rebellious, or lazy.Therefore, the mood is best described as sober.Answer:A. sober