Final answer:
b) By introducing new conflicts and tensions. The conversations that Martha overhears and engages in move the story forward by introducing new conflicts and tensions, and reveal important character backgrounds.
Step-by-step explanation:
The conversations that Martha overhears and engages in move the story forward by introducing new conflicts and tensions.
Dialogues reveal important character backgrounds, which add depth to the story.
For example, in one conversation, Martha learns about the main character's traumatic past, which drives her actions and decisions throughout the story. This dialogue provides crucial information that helps the reader understand the character's motivations and contributes to the development of the plot.