Answer:
Preposition
Step-by-step explanation:
The word "about" functions as a preposition in the given sentence. As a preposition, the word "about" is used to indicate the subject of Adela's favorite story.
"About" as a preposition is used to actually indicate movement to a specific location. e.g. The lizard crawled about in the kitchen.
Also, it is used to indicate the subject of something that is written or spoken. e. g: The story is about gender equality.
A preposition is known to be a word or group of words that are used before a pronoun, noun, or noun phrase to indicate place, time, direction, location or to introduce an object.