Expanding populations and steadily improving communications brought more trade and contact, but also more _______ between social groups.
A. cooperation B. friction C. liberation D. distribution
Expanding populations and steadily improving communications brought more trade and contact, but also more _______ between social groups.
A. cooperation B. friction C. liberation D. distribution
B
【解析】句意：(不断)增加的人口和稳步改善的通讯带来了更多的贸易和交流(机会)，但是也导致了社会团体之间更多的冲突。cooperation合作；friction冲突；liberation解放； distribution分配。“but”说明前后是转折关系，故选B项。