Final answer:
Mr. Darcy listens to Elizabeth's conversations because he is attracted to her intelligence and wit.
Step-by-step explanation:
The reason Mr. Darcy begins to listen to Elizabeth's conversations with other people is because he is intrigued by Elizabeth's intelligence and wit. Mr. Darcy's character, as portrayed in Jane Austen's novel, finds Elizabeth's sharp mind and lively banter engaging, leading him to pay closer attention to her when she speaks with others. This interest grows throughout the book as he learns more about her character through her conversations and interactions, highlighting Austen's use of direct speech and character interaction to reveal more to the reader without explicit narrative description.