阅读理解。 Since her husband died, Mrs. Jackson has lived alone in their big old suburban (郊区的) house. The house was bought by her husband almost fifty years ago. For the sake of safety (为安全起见), her son has tried hard to ask her to sell the house and buy a new and small one in the town, But Mrs. Jackson doesn't like the idea. She says that she has to look after her husband's old house. But recently she often hears stories about unknown people stealing things around here. That was a cold day before Christmas Eve. Around four o'clock in the afternoon, Mrs. Jackson was enjoying the Christmas music when someone knocked at the door. She heard the sound but didn't move. Another knock. Who could it be? Mrs. Jackson was a bit afraid. She decided not to answer the door but keep waiting. One minute another minute and yet another minute. Nothing happened and no more knocks, She walked quietly to the door, and listened. She heard nothing but the wind outside. She slowly unfastened the door and peeped (窥视) through the crack (小缝). She then gave a surprised cry and threw the door wide open! At the door she saw a tall, beautiful Christmas tree! In the tree stood a Christmas card with these words: Merry Christmas! Your new neighbor 1. The house bought by Mr. Jackson is ______. [     ] A. in the town B. small but new C. outside the town D. fifty years old 2. Mrs. Jackson doesn't want to sell the house because ______. [     ] A. it is almost fifty years old B. it is big and old C. she likes to live alone in it D. her husband left it to her 3. Why didn't she move when she heard the knock at the door? Because ______. [     ] A. she was enjoying the Christmas music B. she thought it might be an unknown person C. it was not her son D. she hadn't decided to answer the door 4. When she found it was a Christmas tree, she ______. [     ] A. cried in surprise and pushed the door wide open B. was very surprised to cry C. threw the door away D. went out to stand in the tree