题目

阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。A young man, while traveling through a desert, came across a spring of clear water.【1】water was sweet. He filled his leather container so that he could bring some back to an elder【2】had been his teacher. After a four-day journey, the young man【3】( present ) the water to the old man. His teacher took a deep drink, smiled【4】( warm ), and thanked his student very much for the sweet water. The young man went home【5】a happy heart.After the student left, the teacher let【6从香荚兰豆中提取的一种芳香化合物，其分子式为C8H8O3，遇FeCl3溶液会呈现特征颜色，能发生银镜反应。该化合物可能的结构简式是（ ）A. B. C. D.