单选题 The fifth generation computers, with artificial intelligence, ______ and perfected now.
A. developed B. have developed
C. are being developed D. will have been developed

【正确答案】 C
【答案解析】[解析] 本题中句子的主语computers和谓语动词develop之间是被动关系，故首先排除选项A、B。时间状语now表示谓语是现在正在进行的动作，故选C。