单选题 He can't ______ ignorance as his excuse; he should have known what was happening in his own department.
A. insist B. refer C. plead D. defend

【正确答案】 C

【答案解析】[解析] 动词词义辨析
自己部门的事情不可能不知情。动词搭配plead…as意为“以……为借口”，符合题意。