Read the following question and then pick a category that describes the question.
Question: What feathered cartoon characters do Yugoslavians know as Vlaja , Gaja , and Raja ?
What category is the question in? Choose one from Abbreviation, Entity, Description and abstract concept, Human being, Location, Numeric value. Respond with only the category and no additional text.
Human being
Entity, Human being (assuming Vlaja, Gaja, and Raja are names of specific characters)