Walt Whitman and Emily Dickinson both significantly reshaped the rules of poetic expression, moving away from conventional forms. Their unique styles and themes contributed to the evolution of American poetry. This innovation is what they have in common. ;
Walt Whitman and Emily Dickinson both significantly redefined poetic expression, with Whitman using free verse and expansive themes and Dickinson employing slant rhyme and unique forms. Their creative approaches to poetry illustrate their roles in evolving American literature. Therefore, the correct choice is option A.
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