题目

   A young, dark haired woman appeared in the doorway.    Good morning, children! My name is Mrs. Murray. I am replacing your regular teacher, she said, as she wrote her name on the blackboard. I will enjoy getting to know each of you personally, over the next few months. The children in the class remained silent, as this was totally unexpected. Come on, someone say something, she thought nervously. The children were too quiet. “This probably won’t last long,” she thought, smiling kindly at them, Grade Three students were normally very lively and seldom, if ever silent. “If下列物质不能用于治疗胃酸（含盐酸）过多的是（ ）A．碳酸氢钠B．氢氧化钠C．轻质碳酸钙D．氢氧化铝乳液