阅读下面短文，从短文后所给的A、B、C、D四个选项中选出能填入相应空白处的最佳选项。

    Smiling is the best way of making friends.

    When I was thirteen 1 old, my father found a job in the city. So my family moved there. I also came to a 2 school near where we live. My old school was far away. At first, I did not know anyone in my class. I was very lonely 3 I was afraid to make friends with my classmates. I 4 talk to anyone about my problem, and I didn't want my parents to 5 me.

    Then one day, something good happened. I was sitting at my desk 6 as usual while my classmates were talking happily with each other. At that moment, 7 came into the classroom. I didn't know who he was. He passed me and then turned back. He looked 8 me and, without a word, smiled. Suddenly, I felt happy, lively and warm. That smile changed my life. I started to talk with the other classmates and made friends. Day by day, I became 9 to everyone in my class.

    10 the smile, I have moved on to a new life. Now, I believe that the world is what you think it is. So smile at the world and it will smile back.