单选题 7.  ______ me most was that the young man who had lost both arms in an accident could play the piano beautifully with his feet.
【正确答案】 D
【答案解析】 句意“年轻人在事故中失掉胳膊能够用脚弹奏钢琴，这让我震惊”。What引导的主语从句。