While in bed the doctor was telephoned to go back to the hospital because of ______ case.
 
【正确答案】 D
【答案解析】 treatment“待遇,处理,治疗”;operation“操作,手术”;incident“事件,事变”;emergency“紧急情况,突发事件”。根据句意,an emergency case意为“急症病例”,故答案为D。