A：Al2（SO4）3═2Al3++3SO42﹣
B：NaHCO3═Na++H++CO32﹣
C：NaHSO4═Na++HSO4﹣
D：KClO3═K++Cl﹣+3O2﹣
句中成语使用完全正确的选项是：（ ）
I have a pencil box. It's blue. There are lots of things in it. I have a pen. It's red and long. I like it. I have three pencils. They are short. I have a ruler. It's big. I have an eraser. It's small.
