【单选题】设单循环链表中结点的结构为(data, next),且rear是指向非空的带头结点的单循环链表的尾结点的指针。若想删除链表的首元结点,则应执行的操作是( )。
A.
s = rear; rear = rear->next; free(s);
B.
s = rear->next; rear->next = s->next; free(s);
C.
s = rear->next ->next ; rear = rear->next->next; free(s);
D.
s = rear->next->next; rear->next->next = s->next; free(s);