阅读下面短文，从每题所给的A、B、C、D四个选项中，选出能正确回答所提问题或完成所给句子的最佳答案。
Bill was a boy of 15. His parents went gambling (赌博) all day and all night. Nobody cared about him. He couldn't pass the exams. So his teachers didn't like him, neither did his classmates play with him.
Bill often slept in class because his heart was not in school. He almost gave himself up.
One day, Miss Jones, a new teacher, came to Bill's class. She was a loving and beautiful woman. Bill was in love! For the first time in his young life, he couldn't take his eyes off his teacher.
It was Miss Jones' class. She was asking a question. "I'd like the smartest boy to answer my question." Then she said loudly, "Bill, please!"
Bill was surprised. And he stood up without a word.
"Just try it! I believe you can!"
After school, Miss Jones had a long talk with Bill. She told him that she cared about him and believed in him.
Bill thought a lot that evening. From then on he arrived at school on time every day. Miss Jones helped him with his homework in the afternoon. She even cooked delicious food for him. She told Bill, "Nothing is impossible if you put your heart into it."
Later, Miss Jones gave them another exam. Bill did it with all his heart. He was very amazed to find that he had passed the exam. Now Bill discovered that not only could he learn, but also he could do it well. A change took place in Bill's heart.
You see that one teacher saved one boy. It's really simple.
