阅读下面短文、从每题所给的A、B、C三个选项中选出能填入空白处的最佳选项。

Now, Jack is at the lost and found office（失物招领处） of a park. He comes  1  a schoolbag. It's not  2 . He found it in  3  park. 

He waited for twenty minutes 4 no one came. "The owner （主人） of the 5 must be worried （担心的） . So I 6 it here, " Jack says to Ms. Read, a worker at the office.

You're 7 to do so. Please write down your phone number. " says Ms. Read. "When the man comes to get it, he can call to 8 you. "

"Jack answers, " Oh, no! I just 9 to return （归还） it to its owner!" With these words, Jack leaves 10.

"What a good child!" says Ms. Read as Jack walks away.