阅读下面短文，掌握其大意，然后从每题所的A、B、C、D四个选项中选出最佳选项，使文章完整、通顺。
It was two days before Christmas, and David wanted to give a card to everyone in his class. He opened the bag and looked 1. "What are you looking for?" his mom asked. "Ms. Ross gave us a 2 of everyone in the class, "said David." I can't find mine. If I don t have my list, I won't know what names to put on the cards."
"Take 3 out and we'll look together," suggested Mom. They shook out all his books and 4 all the pockets in his bag, but no Christmas list. "Now I can't give out cards at school, "David said sadly.
"Don't 5 so easily, said Mom. She took a piece of paper and asked him how many children are in his class. "Seventeen," answered David "I'll never 6 them all."
"Wait, "said Mom, numbering the paper one to seventeen." Now, who do you often play with?" "Brian, Todd and John." She wrote down their 7. "And who sits in the first row in your classroom？”“Hmm…Angie, Jill and Brad." David tried to remember what his 8 looked like and who sat where, " And Rebecca, Travis and Erin in the second row." David's mom wrote as fast as she could.
Now, they had 9 names. Who had he missed? David thought hard.
"Why don't you write out the 10 that you have names for?" said Mom. "Maybe you'll think of the 11 name while you're writing."
David picked out a card. He 12 it and then put it into the envelope. He did this sixteen times. "13 is missing?" One more time he thought about who sat where in his classroom.
14 he said, "I know! I know who is missing from the list!"
"who?" said Mom.
"We forgot 15!" David said. "I'm going to wish me a Merry Christmas, too.
