Ireland is unique among European countries for ______.

Ireland is unique among European countries for ______.
A、its small population
B、its beautiful scenery
C、its rich natural resources
D、its century-long population decline
【正确答案】：D
【题目解析】：爱尔兰在欧洲国家里是独一无二的，因为人口下降长达一个世纪。