阅读下面这首古诗，完成两小题。
                                                                                                              齐安郡中偶题
                                                                                                               （唐）杜牧
                                                                                           两竿落日溪桥上，半缕轻烟柳影中。
                                                                                           多少绿荷相倚恨，一时回首背西风。
                                                                                                             暮热游荷池上
                                                                                                            （宋）杨万里
                                                                                             细草摇头忽报侬，披襟拦得一西风。
                                                                                             荷花入暮犹愁热，低面深藏碧伞中。

下列图片反映的共同主题是（      ）
 
                     虎门销烟                          北洋舰队“致远号”战舰             义和团旗帜