Concept:An allegory is a literary device in which characters, events, and settings carry deeper symbolic meanings beyond their literal surface.
Explanation:In an allegory, the story works on two levels at once: the literal events and the hidden symbolic message.
The characters and incidents are not meant to be taken only at face value; they represent abstract ideas such as morality, politics, religion, or social issues.
For instance, in George Orwell's
Animal Farm, the farm animals symbolize historical figures and events of the Russian Revolution.
This perfectly matches the description given in the question: a work where characters and events are used as symbols.
The other options can be ruled out. Characterization simply refers to the way an author reveals a character's personality.
A metaphor is a direct comparison between two unlike things, not a full narrative built on symbols.
Parallelism is a structural device that involves balancing similar grammatical or thematic elements.
Only allegory fits the definition of a complete work whose elements act as symbols bearing a deeper meaning.
Answer:B. allegory.