While income worry is _____ rather commen problem of the aged,loneliness is another problem that _____aged parents may f
问题描述：
While income worry is _____ rather commen problem of the aged,loneliness is another problem that _____aged parents may face.
请填入适当的冠词（或者根据需要不填）,并说明理由!
答
a 一个普遍存在于老年人群的问题
不填泛指上了年纪的父母,不是特指某一对父母