Final answer:
Darcy's letter to Elizabeth contains justifications for his behavior towards Mr. Wickham and Mr. Bingley, revealing Wickham's deceit and his protection of Georgiana from an elopement.
Step-by-step explanation:
The letter that Darcy gives Elizabeth contains a detailed explanation and defense of his actions regarding his dealings with Mr. Wickham and his role in dissuading Mr. Bingley from pursuing a relationship with Jane Bennet. Darcy admits to advising Bingley based on his belief that Jane's affections were not strong and out of concern for his friend's well-being. As for Wickham, Darcy reveals Wickham's true character, mentioning his gambling debts and his attempt to elope with Darcy's younger sister, Georgiana, for her fortune. This letter plays a critical role in Pride and Prejudice as it brings a turning point in Elizabeth's feelings towards Darcy, shifting from prejudices to understanding and respect.