Scholars who once thought Native American literatures were solely oral narratives recorded by missionaries or anthropologists now understand this body of work to consist of both oral literatures and the written works of Native American authors, who have been
publishing since 1772.

A. Scholars who once thought Native American literatures were solely oral
narratives

B. Scholars thinking of Native American literatures once solely as oral narratives,and

C. Scholars who once had thought of Native American literatures solely as oral narratives and

D. Native American literatures, which some scholars once thought were solely oral narratives

E. Native American literatures, which some scholars once, thinking they were solely oral narratives

OA is
A

Please explain why other options are incorrect.