单选题
. ①Ralph Ellison was passionately interested in the visual arts. ②He immersed himself in Harlem's art scene in the 1930s, even apprenticing with sculptor Richmond Barthé for a time. ③Yet he was wary of projects aiming to provide a visual rendering of his novel
Invisible Man. ④He reluctantly allowed Franklin Library to publish two illustrated versions of the novel but found the results disappointing and repeatedly rejected proposed film versions of the book. ⑤Despite his involvement in visual arts, Ellison insisted that only language could capture the complexity of American identity. ⑥This complexity consisted of the tension arising from the collision of the United States' written ideals, as outlined in the founding documents, and the historical and contemporary experiences molding the national consciousness.
27. It can be inferred that the author mentions Ellison's apprenticeship with Richmond Barthé primarily in order to ______