A large apartment building in a city was assessed by a city environmental bureau for the comparatively high consumption of electricity in the building, and the landlord was threatened with a possible fine if the consumption did not drop significantly in a specified period. While all built-in appliances and lighting in common areas are energy efficient, the landlord found, upon doing an inspection, many residents were using older portable heaters that are not very energy efficient. The landlord decided to send each resident a detailed letter about the electric energy consumption of these older portable heaters, recommending newer more energy efficient models that could be purchased at local stores. He hopes the letter will motivate enough residents to buy more energy efficient heaters.
Which of the following, if true, would provide most support for the prediction that the landlord's letter will have its intended effect?
【选项】Residents pay for their own monthly electrical use, and the rates in this city are high, so consuming less electricity would result in a sizable monthly savings.