题目解析:
题干提问“社会的差异性发展会有什么影响”。
由 social difference 定位第2段第1句 social differences (social hierarchy) that increased the intensity of their foraging,由 intensity of their foraging 前半句的 initial agriculture evolved out of intensified foraging,
即 social differences --> foraging intensity --> initial agriculture,对应选项 A。
故选 A。