设单循环链表中结点的结构为(data,link),且rear是指向非空的带表头结点的单循环链表的尾结点的指针。若想删除链表第一个结点,则应执行下列哪一个操作
s=rear; rear=rear->link; delete s;
rear=rear->link->link; delete rear;
s=rear->link->link; rear->link->link=s->link; delete s;
rear=rear->link; delete rear;