1. In the context of the passage the highlighted sentence serves to

A. explain the broader rationale for a conclusion described in the preceding sentence

B. suggest some of the drawbacks of the riverbank location of the villages described in the

C. acknowledge information that appears to undermine a description attributed to Orellana

D. introduce a principle that appears to be contradicted by the agricultural development of

E. give a reason for an upward revision in earlier estimates for premodern Amazonia