Answer:
option d: they fly away
Step-by-step explanation:
The speaker in the poem stated that he will "awake some day / To find they have flown away?. this flight represent for him the loss of youth
The run-on lines shows movement and reflect the swans' flight. They form a ring – a symbol of eternity – may shows this reminds the author that while he might change, the swans remain the same, and even make the same patterns in the sky every year.