单选题When he arrived  he 

问题补充：

单选题Whenhearrived,hefound____theagedandthesickathome.A.nothing butB.none butC.none other thanD.no other than

答案：

B解析空格后the aged and the sick, 等于the old people and the sick people,所以but前应用表示人的不定代词。