Walt Whitman was a pioneering figure of American poetry. His innovation first all lies in his use of ______, poetry without a fixed beat or regular rhyme scheme.

Walt Whitman was a pioneering figure of American poetry. His innovation first all lies in his use of ______, poetry without a fixed beat or regular rhyme scheme.

A.blank verse

B.heroic couplet

C.free verse

D.iambic pentameter

正确答案是C