We do no pay a fixed amount for electricity, gas or telephone calls irrespective of how much we use. How is it then that some people are still expected to do so in the case of water? People who use relatively little water should no longer be required to subsidize those who use a great deal. Water meters should therefore be introduced in all regions as soon as it is feasible to do so.

Which one of the following best illustrates the principle underlying the argument above?

A. Our town is providing a series of recycling banks so that residents who wish to recycle household waste can do so.
B. When we eat out as a group we divide the bill by the number of people dining.
C. The government is paying compensation to house owners whose properties were damaged in the floods.
D. The new road is going to be financed by a toll system rather than out of taxation.
E. People who have difficulty paying the annual television license fee may pay in monthly instalments.