“三大产热营养素”是指（　　）

某无色溶液中可能含有H⁺、OH^﹣、K⁺、NO₃^﹣，加入铝粉后，只产生H₂．试回答：

名著阅读：读下面的小诗，回答问题。
                                                                                                 小小的花，
                                                                                                 也想抬起头来，
                                                                                                 感谢春光的爱——
                                                                                                 然而深厚的恩慈，
                                                                                                 反使她终于沉默。
                                                                                                 母亲啊！
                                                                                                 你是那春光吗？