C. He is prepared to die and regrets that he will not grow old gracefully.
"This push will cheer me ever, or disseat me now. I have lived long enough. My way of life is fall'n into the sere, the yellow leaf, and that which should accompany old age."
He is basically saying how he isn't afraid to die, yet he still wishes that he could live a long, happy life, and grow old like any other man would. The phrase "the yellow leaf", was what gave it the immediate thought of age, because yellow, red, and brown leaves can symbolize age, decay, and being long lived.
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