Answer:
the downfall of the protagonist.
Step-by-step explanation:
A tragedy is a form of drama that has as subject human suffering. One of the most significant elements of a tragedy is the element of catharsis. This refers to the relief and pleasure that audiences feel when they witness a tragic story. The downfall of the protagonist is the main element that causes this paradoxical catharsis. Therefore, the plot events of a tragedy are structured in a way that reveals the downfall of the protagonist and allows the audience to feel this purification of emotions.