阅读短文，选择正确的答案。

Sarah and her father are in a train. Sarah likes to stand and puts her head out of the window. Her father says, “Sit down! Don't put your head out of the window!” But Sarah goes on putting her head out of the window. Her father takes Sarah's cap quickly and says, “You see, your cap has flown. Sit down! Perhaps (可能), your cap will come back. ” Sarah is afraid and she sits on chair quickly. Sarah's father puts the cap on Sarah's head. Oh! It is wonderful! Sarah is happy. She takes her father's cap quickly and throw it out of the window. ” Now your turn, Dad!” Sarah says happily.