（）是指保险人已放弃某种权利的，日后不得再向被保险人主张。
A.确认保证
B.承诺保证
C.弃权
D.禁止反言
参考答案：D
Fever is a ________of many illnesses. So I suggest you take it seriously and see a doctor as soon as possible.
A．message
B．symptom
C．label
D．clue
机夹可转位式车刀的主要优点有哪些？
