Answer:
b. Cities tend to require very large inputs of energy and materials resulting in large outputs of waste.
Explanation:
Modern cities require much more energy because of the increase in population resulting in the demand for inputs of energy and materials to be particularly high. But because this relationship to waste output is inversely proportional, there will also be large outputs of waste. Cities need to place a waste management system in their towns in order to combat this unsustainable way of living,