Answer:
(A) Because the regulation effectively reduced the price of cool air, consumers with sufficiently elastic demand might have bought substantially more of it.
Explanation:
If the demand for energy services remains constant, improving energy efficiency will reduce energy consumption and carbon emissions. However, many efficiency improvements do not reduce energy consumption by the amount provided by simple engineering models. This is because they make energy services cheaper and therefore increases the consumption of those services.
For example, since low-fuel vehicles make travel cheaper, consumers can choose to drive further, thus offsetting some of the possible energy savings. Similarly, an extensive historical analysis of improvements in technological efficiency has conclusively demonstrated that improvements in energy efficiency were almost always overcome by economic growth, which resulted in a net increase in resource use and associated contamination.