Answer:
The best illustration of the principle underlying the argument is:
B. When we eat out as a group, we divide the bill by the number of people dining.
This example demonstrates the principle of fairness and individual responsibility. Just as each person pays for their own meal in a group setting, the argument suggests that individuals should pay for their own water usage based on the amount they consume. It emphasizes the idea that people who use relatively little water should not be obligated to subsidize those who use a significant amount. Similar to dividing the bill at a restaurant, introducing water meters allows for a fair distribution of costs based on individual usage.