The author most likely states that "cultural borrowing is of course, old news" primarily to A. acknowledge that in itself the existence of intertribal tendencies at powwows is unsurprising B. suggest that native Americans' use of English in powwows should be accepted as unavoidable C. argue that the deliberate distinction of intertribal and traditional dances is not a recent development D. suggest that the recent increase in intertribal activity is the result of native Americans borrowing from non-native Americans E. indicate that the powwow itself could have originated by combining practices drawn from both native and non-native American cultures