Answer: The right answer is the D) Excited.
Explanation: Just to elaborate a little on the answer, it can be added that the tone of the excerpt refers to the attitude of the author towards the events that she is describing — the chance encounter between two teenagers at an ice skating rink. That attitude is clearly an attitude of excitement. The author was observing the main character and she describes her reaction when a young boy invited her to skate with him, and the feelings of happiness and enthusiasm that that unexpected and warm invitation arose in her.