The doctor ________ is leaving for Africa next month．
A.the nurse is talking to himB.whom the nurse is talkingC.the nurse is talking toD.who the nurse is talking在线课程C
解析：
该题doctor后面为定语从句，引导词在从句中作宾语，应用关系代词whom/who/that，或被省略。A项him重复；
B项和D项缺少介词to。