阅读理解。 I have a friend. He has a large police dog. The dog's name.is Jack. Police dogs are often very clever. Every Sunday afternoon my friend takes Jack for a long walk in the park. Jack likes the long walk very much. One Sunday afternoon, a young man came to visit my friend. They talked and talked. Soon it was time for my friend to take Jack for his walk. But the visitor was still there. Jack became very worried about his walk in the park. He walked around the room a few times, and then sat down directly in front of the visitor and looked at him. But the visitor paid no attention. He went on talking. Finally Jack could no longer stand it. He went out of the room and a few minutes later he came back with the visitor's hat in the mouth. (     )1. A. The writer's friend has a police dog named Jack. B. The writer's friend's name is Jack. C. The writer's name is Jack (      )2. A. Every Sunday afternoon the writer's friend goes to the park for a walk. B. Every Sunday afternoon the dog goes to the park for a long walk. C. Every Sunday afternoon the writer s friend and his dog go to the park for a long walk. (      )3. A. The visitor was old. B. The visitor was young. C. The visitor was neither old nor young (      )4. A. The visitor paid attention to the dog. B. The visitor paid a little attention to the dog. C. The visitor paid no attention to the dog. (      )5. A. The visitor came back with his hat in his hand. B. The dog came back with the visitor's hat in his mouth. C. The writer s friend came back with the visitor's hat in his hand.