Final answer:
In the story "Stone Soup" by Elsa Southern, the traveler convinces the villagers to contribute ingredients to make a delicious soup.
Step-by-step explanation:
In the story "Stone Soup" by Elsa Southern, the traveler responds to the challenge of getting food by convincing the villagers to contribute ingredients. He does this by telling them that he can make a delicious soup with stones, but it would be even better if they could add some vegetables or spices. The villagers become interested and start contributing various ingredients to the pot, resulting in a delicious and hearty soup that they all enjoy together.