A. turned over B. turned on

C. turned off D. turned down

【答案】D

【解析】句意：——你看上去不高兴，怎么了？——我的建议又被拒绝了。考查动词短语辨析。turn down拒绝，故选择D项。turn over颠倒，倾覆；turn on打开；turn off关掉。