第15题: [单项选择]The incidence of this disease has been greatly reduced thanks to our health care pro- gram. A. seriousness B. frequency of occurrence C. mortality D. cure rate 参考答案:B 答案解析:[解析] 本题中,incidence意为“发生(率);影响;影响的方式[范围,程度]”。四个选项中,frequency of occurrence意为“发生频率”;seriousness意为“严肃,认