Final answer:
The author uses irony to contrast the protagonist's innocence with the harsh reality, emphasizing the theme of relying on knowledge and training.
Step-by-step explanation:
The author uses irony in the story to contribute to its meaning by contrasting the protagonist's innocence with the harsh reality. This irony helps to emphasize the theme of relying on knowledge and training rather than second-guessing oneself. For example, the protagonist in the story may have thought he was well-prepared for the examination, but the reality of the situation proves otherwise. This use of irony adds depth to the story and highlights the importance of self-awareness.