阅读下面短文，从短文后各题所给的四个选项A、B、C、D中，选出可以填入空白处的最佳选项。Shailyn Ryan is a 9- year- old girl from Massachusetts. That day, during lunch in the school dining hall, she noticed1 unexpected happening. Her friend Keira held a hand to her own throat without a word. Her face rapidly turned red, then blue. Though Keira was unable to 2 , Shailyn knew she was choking（噎住）.
Immediately, Shailyn jumped from her seat and stood behind Keira. She pushed Keira a bit forward, put her arms 3 Keira's waist（腰部）, then pressed as hard as she could.
It wasn't long before a hot dog piece popped（突然弹出）up from Keira's throat. Thanks to her 4 action, Keira was free to breathe again.
"I didn't really think about it—I just did it," said Shailyn. "I wasn't 5 at all, and I knew that I had to do something fast, so I did." And she did it just right.
The most6 part of the story is that Shailyn knew the Heimlich maneuver（海姆立克操作法）just for less than 24 hours. Only the night before, she attended "Home Alone" kids 7 class. At the class, she and several other children learnt basic first aid and practised 8 to do the Heimlich maneuver on each other. Clearly, Shailyn was a really fast 9 ! She was able to take what she'd learnt the night before and 10 it in real life.
A few days later, Shailyn was given an award by the school master Jill Barnhardt. "We're sure to 11 Shailyn for her actions in such situation," Barnhardt said. "Shailyn took actions 12 . Her response to her friend's suffering was effective. She is simply a 13 ."
Shailyn was also excited to get a personal tour of a hospital 14 she dreamed of becoming a doctor. "I want to 15 more people," she said. "That would be cool to work in a hospital."
