in 1942 thE us Anthropology stuDEnt ConCluDED thAt thE siriono A wErE unusuAlly AggrEssivE AnD CruEl. B hAD hAD thEir wAy oF liFE DEstroyED By invADErs. C wErE An ExtrEmEly primitivE soCiEty. D hAD only rECEntly mADE pErmAnEnt sEttlEmEnts.