Although many customers do not make a sufficient effort to conserve water, water companies must also be held responsible for wasteful consumption. Their own policies, in fact, encourage excessive water use, and attempts at conservation will succeed only if the water companies change their practices. Which of the following, if true, would most strongly support the view above? ['Most water companies keep detailed records of the quantity of water used by different customers.', 'Federal authorities limit the range of policies that can be enforced by the water companies.', 'Most water companies reduce the cost per unit of water as the amount of water used by a customer increases.', 'The price per unit of water charged by the water companies has risen steadily in the last 10 years.']