设rear是指向非空带头结点的循环单链表的尾指针，则删除起始结点的操作可表示为( )

A．s=rear;

B．rear=rear—＞next;rear=rear—＞next; free(rea;free(;

C．rear=rear—＞next—＞next;

D．s=rear—＞next—＞next;free(rea; rear—＞next—＞next=s—＞next;free(;