Clarification:
I found the description of the event to complete the exercise online.
Answer:
He doesn't really understand what's going on, but he wants to be a part of it.
Step-by-step explanation:
To complete this exercise, you have to select the correct answer after you read the description of the even.
The correct answer is "He doesn't really understand what's going on, but he wants to be a part of it" because Charlie says that he doesn't understand what the doctors are saying: "I didn't get all the words but it sounded like..." and then he gets excited when the doctor says they would use him: "When he said that I got so exited I jumped up and shook his hand...".