Answer:
C. Reflective
Step-by-step explanation:
A reflective mood is one that is characterized by deep thoughts. The poet in this stanza thinks deeply of the remaining number of years he has left to spend on earth. This is a sober thought because it makes one think back on the past years spent and how they were spent. It also brings the sudden realization that the person now has limited time and must make the best use of it.
Therefore, the tone created by the poet is a reflective one.