The correct answer is D. obsessed.
An obsessed person is someone who is very interested in or concerned with something. In this case, Elsie is very interested in gardening. She is so interested in gardening that she spends a lot of time and energy on it. She may even neglect other aspects of her life in order to garden.
The other options are not correct because they do not accurately describe Elsie's behavior. Crazy is not a good word to use to describe someone who is simply very interested in something. Fantastic is a word that is used to describe something that is very good or impressive. Enthusiastic is a word that is used to describe someone who is very eager or excited about something.
It is possible that Elsie is all of these things, but the question only asks for one word to describe her behavior. The word that best describes her behavior is obsessed.
