Shelley’s greatest achievement is his four-act poetic drama（）， which is an exultant work in praise of humankind’s potential.

Shelley’s greatest achievement is his four-act poetic drama（）， which is an exultant work in praise of humankind’s potential.
A、Adonais
B、Queen Mab
C、Prometheus Unbound
D、A Defence of Poetry
正确答案：C