Could you tell me something about the boy who helped you just now? -- Sorry I know no

问题补充：

-- Could you tell me something about the boy who helped you just now?

-- Sorry, I know nothing about him. We are.

A. friends

B. neighbors

C. classmates

D. strangers

答案：

A. friends

B. neighbors

C. classmates

(答案→)D. strangers

解析：本题的含义是我对他一无所知，那么我们应该是陌生人，stranger是陌生人的意思，故本题选D。