They suggested that the professor just now chairman of the meeting.
A. referring to；was made
B. referring to；be made
C. referred to；be made
D. referred to；was made
网友回答
A. referring to；was made
B. referring to；be made
(答案→)C. referred to；be made
D. referred to；was made
解析：C 考察非谓语动词和虚拟语气。句义：他们建议刚才所提到的那位教授成为会议的主席。Referred to是过去分词短语修饰名词the professor，suggest后面接宾语从句要使用should+动词原形，should可以省略。