Final answer:
Della's decision to sell her hair to buy a gift for Jim and their subsequent exchange of gifts are key to the development of the plot in 'The Gift of the Magi'. Their sacrifices reveal the theme of selfless love and propel the story towards its ironic climax.
Step-by-step explanation:
In The Gift of the Magi, Della's choices and interactions are central to the development of the plot. The story is structured around Della's decision to sell her most prized possession, her long, beautiful hair, to buy a platinum fob chain for her husband Jim's watch, considering it a perfect gift. This act of self-sacrifice for the sake of love sets the stage for the story's ironic climax.
The plot thickens when Jim comes home to see Della's shorn hair and reveals that he has sold his watch to buy her a set of combs for her hair. This mutual sacrifice, where both characters have given up their dearest possessions to buy gifts for each other, creates a poignant twist and brings the central theme of the story to a climax. The interactions between Della and Jim reveal their deep love for each other and mirror the theme of selfless giving, enhancing the emotional impact of the story.
Characterization is employed by O. Henry through Della's actions and her interaction with the hairdresser, where her determination and sense of sacrifice are further highlighted. Additionally, the setting intensifies the tension, particularly due to the couple's economic hardship, making their sacrifices even more profound.