During Yeats's（）stage of his poe

During Yeats's（）stage of his poetic creation, he has developed a tough, complex and symbolical style.
A、first
B、second
C、first and second
D、last
【正确答案】：D
【题目解析】：在他诗歌创作的最后一个阶段中，Yeats发展出了一种坚韧、复杂和象征主义的风格。