Which of these best describes the tone of the following passage from Helen Keller's autobiography?

I learned a great many new words that day. I do not remember what they all were, but I do know that mother, father, sister, teacher were among them--words that were to make the world blossom for me, 'like Aaron's rod, with flowers.' It would have been difficult to find a happier child than I was as I lay in my crib at the close of that eventful day and lived over the joys it had brought me, and for the first time longed for a new day to come.

regretful
hopeful
depressed
all of these