题目解析:
A选项用income定位到该段第三句:These families were pensioned off (given a sum of money to live on) or simply had their revenues taken away or restricted.对应A选项;
B选项用their sons对应该段第三句:...their sons were enticed away to schools for district office later to be posted in some faraway province.对应B选项;
C选项原文中没有提及;
D选项用rural population对应该段倒数第二句:
Local rulers could no longer protect their relatives and attendants in legal cases, and with the ending in 1905 of the practice of forcing peasant farmers to work part-time for local rulers, the rulers no longer had a regular base for relations with rural populations. 对应D选项。