The correct answer is B. Autumn is a symbol of advancing age.
Explanation:
In the excerpt presented from "The Wild Swans at Coole" by William Butler Yeats the author mainly describes the changes of the autumn through multiple years. Dor doing this, the author fist states "The nineteenth autumn has come upon me Since I first made my count…", these verses suggest around 19 years have passed for the author, besides this it is stated during this time everything has changed as the author claims "All’s changed since I, hearing at twilight, The first time on this shore…". The previous ideas imply for the author each autumn implies that time has passed and also that the author itself has grown old which causes the author to feel mainly nostalgic. According to this, the time of the year shows the autumn is a symbol of advancing age.
