As soon as she entered the room , the girl caught sight of the flower _ by her morther A buying B being boughtC were bought D bought答案D 请作具体分析
热心网友
the girl caught sight of the flower (which was)bought by her morther 省略
热心网友
花是被买的，应用被动的形式，这里是过去分词短语修饰前面的名词。
热心网友
选A!!!