Answer: A) rising action.
Step-by-step explanation: In a story, the rising action is a series of relevant incidents that create suspense, interest, and tension in a narrative. It includes all decisions, characters' flaws, and background circumstances that together create turns and twists leading to a climax (which is the point of highest tension in the story). The given sentence is an example of a rising action because it demonstrates an event that causes a reaction in Martha and that will probably lead to the climax of the plot.