第36题: [单项选择]During the Middle Ages, productivity of labour______. A. was a primary concern of society. B. was hampered by class relationships. C. went beyond levels reached by the Greeks. D. both increased and decreased. 参考答案:B 答案解析:推理判断题。文章第二段和第三段都从理论上解释了社会结构对生产力发展所起到的阻碍作用,所以,选项B为正确答案,选项A、C和D的内容;文章并未提及。