A. follow a direct line of ascent B. also appeal greatly to adults C. are not characterized by technological progress D. reflect the pace of social progress 参考答案:C 答案解析:[解析] 事实细节题。[C]“不以技术进步为特点”与第四段第一句后半部分以及第三句后半部分的含义一致(technological progress同时和technological leaps,inve