Helping others is a habit,    you can learn even at an early age

A．it

B．which

C．what

D．that

在保险合同变更中，保险代理人保险人双方权利和义务的变更，即保险代理合同条款事项的具体变更，被称为()

A.内容的变更

B.客体的变更

C.责任的变更

D.主体的变更