单项选择题
单向链表的每一个节点都有一个指向它的后续节点的指针link，现有节点p和q，节点q在节点p的前面，要删除节点p，正确的操作应该是
A．q↑. link: =p↑．link;
B．p↑. link: =q↑. link;
C．q↑. link: =p; p↑. link: =q;
D．q: =p↑. link; p↑. link: =q↑. link;
B．p↑. link: =q↑. link;
C．q↑. link: =p; p↑. link: =q;
D．q: =p↑. link; p↑. link: =q↑. link;
Y，则X→Y'