( 11 )双链表的每个结点包括两个指针域。其中 rlink 指向结点的后继, llink 指向结点的前驱。如果要在 p 所指结点前面插入 q 所指的新结点,下列哪一个操作序列是正确的?
A.rlink ↑ .llink:=q ; p ↑ .rlink:=q ; q ↑ .llink:=p ; q ↑ .rlink:=p ↑ .rlink ; B.llink ↑ .rlink:=q ; p ↑ .llink:=q ; q ↑ .rlink:=p ; q ↑ .llink:=p ↑ .llink ; C.llink:=p ; q ↑ .rlink:=p ↑ .rlink ; p ↑ .rlink ↑ .llink:=q ; p ↑ .rlink:=q ; D.rlink:=p ; q ↑ .llink:=p ↑ .llink ; p ↑ .llink ↑ .rlink:=q ; p ↑ .llink:=q ;