题目

     It was Monday. Mrs. Smith's dog was hungry, but there was not any meat in the house. Considering that there was no better way, Mrs. Smith took a piece of paper, and wrote the following words on it: “Give my dog half a pound of meat.” Then she gave the paper to her dog and said gently: “Take this to the butcher(屠夫). And he's going to give you your lunch today.”     Holding the piece of paper in its mouth, the dog ran to the butcher's. It gave the paper to the butcher. The butcher read it carefully, recognized that it was really the lady's handwriting and soon di在北方的冬季，常见的几种物态变化现象中，属于凝华的是（　　）A．室外冻冰的衣服变干B．房间窗户玻璃的内表面出现冰花C．湖面结了厚厚的一层冰D．正在跑步的人，口中呼出“白气”