A. p-rlink-llink = p-rlink;p-llink-rlink = p-llink; delete p;
B. p-llink-rlink = p-rlink;p-rlink-llink = p-llink; delete p;
C. p-rlink-llink = p-llink;p-rlink-llink-rlink = p-rlink; delete p;
D. p-llink-rlink = p-rlink;p-llink-rlink-llink = p-llink; delete p;