Younger children are particularly vulnerable to concussions because of the state of their developing brain.
Answer: Option C
<u>Explanation:</u>
The text is about the talking done about concussion. Concussions are the head injuries that the children get when they are involved in some kind of sport. The text says that the younger children are more vulnerable to the concussion because they have still a developing mind.
They are more vulnerable to the injury as compared to a developed mind. They have more chances of concussion interrupting with their normal working of the neurological order.
I believe that the most fitting answer for this question would be the word "giggle." Even if you have never read this story before, you can assume from the girls' laughter that what is about to happen is going to be amusing and fun. This word is the best hint that something amusing is going to happen. I hope this helps.
I believe the answer is B ^^
Normality or familiarity maybe???