下列植物中属于国家一级保护植物的是(     )。

 阅读下文，回答相关问题。

                                                                                                                                  春山夜月
                                                                                                                                  唐·于良史
                                                                                                                 春山多胜事，赏玩夜忘归。
                                                                                                                 掬水月在手，弄花香满衣。
                                                                                                                 兴来无远近，欲去惜芳菲。
                                                                                                                 南望鸣钟处，楼台深翠微。

将紫色石蕊试液滴入稀盐酸中，溶液的颜色变成（   ）