-----where has his brother been ?
------No one knows. He has returned home safely but his missing made the police .
A. to puzzle
B. puzzling
C. puzzled
D. be puzzled
网友回答
A. to puzzle
B. puzzling
(答案→)C. puzzled
D. be puzzled
解析：考查非谓语动词做宾语补足语。Puzzled感到困惑的；修饰表示人的名词。Puzzling令人困惑的，修饰表示事物的名词；句意：他已经安全到家里但是他的失踪让警方很困惑。