The correct answer is C. The swans in Yeats's "The Wild Swans at Coole" symbolize the speaker's youth. As the name of the poem is "The Wild Swans at Coole", it is no a surprise that swans were everywhere. They are a symbol of beauty, but also of energy and permanence. Although swans play a very important role, they also remind him of the pains of getting old and the inevitability of death.