Marissa is using rationalization in her statement when she justifies breaking the toy by focusing on the other person's behavior and her frustration. However, none of the options provided (compensation, denial, reaction formation, projection) directly fits this explanation. If you are looking for the closest option from those listed, it may lean towards denial as she seems to dismiss the importance of breaking the toy by justifying her actions based on how she feels wronged.
However, please note that the best fit in the context of her defense mechanism would actually be rationalization, though it's not one of the listed options.