The correct answer is d. the growing economic prosperity through industry. In F. Scott Fitzgerald's novel The Great Gatsby, Gatsby's car is a symbol of the growing economic prosperity and industrialization of the United States during the Roaring Twenties. The car is described as a "rich cream color, bright with nickel, swollen here and there in its monstrous length with triumphant hat-boxes and supper-boxes and tool-boxes, and terraced with a labyrinth of windshields that mirrored a dozen suns." This description emphasizes the car's wealth and opulence, and suggests that it is a product of the thriving economy of the time.
Gatsby's car also symbolizes the excess and decadence of the era, as it is described as being "swollen" and "monstrous" in its size and extravagance. This reflects the excesses of the time, as many people became wealthy through illegal means, such as bootlegging, and spent their money on lavish parties and extravagant possessions. Gatsby's car, with its "triumphant hat-boxes" and "terraced" windshields, represents this excessive lifestyle.
Overall, Gatsby's car symbolizes the growing economic prosperity and industrialization of the United States during the Roaring Twenties, as well as the excesses and decadence of the era.