单选题 His teacher ______ concern about the progress he had made at school.
A. expressed B. exported C. exploded D. exposed

【正确答案】 A

【答案解析】[解析] 本题考查同为ex开始的动词的辨析。express表达；export出口；explode爆炸；expose 暴露，显露。根据句意，选项A正确。