Ju Hua Tai is a popular song among young people, ___were often heard singing it in Karaoke.

A．which

B．who

C．that

D．what

人身保险的保险金额是由投保人与保险人双方在法律允许的范围与条件下，协商约定后确定的。采取这种确定方式的原因是()。

A.人的生命价值很难用货币来计价

B.人身保险受到人的年龄约束

C.人身保险常涉及第三方

D.人身保险的医疗费用是不确定的