On average, one tribe of amazonian indians has been lost each year of the twentieth century. the fundamental basis for this destruction has been

Had to look for the options and here is my answer.
It is said that one tribe of the Amazonian Indians has been missing each year during the twentieth century, and the main basis that this destruction has been occurring is ETHNOCENTRISM AND THE GREED OF NON-INDIANS. Hope this answers your question.