Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage.

In Western countries, electricity, gas, and water are not (11) but necessities. Companies now realize that consumers want (12) that will not only work effectively, (13) save money.

For most North American households, lighting (14) for 10 percent to 15 percent of the electricity (15). However, this amount can be (16) by replacing an ordinary 100-watt light bulb with an energy-saving bulb. These bulbs use a (17) of the electricity of standard bulbs and last eight times (18). Therefore, consumers can save about US$7 to US$21 per bulb. In Europe, there is a labeling scheme for refrigerators, freezers, washing machines and tumble dryers. The label tells the consumers how much energy efficiency each model has, compared (19) other appliances in the same category. Ultimately, these innovations will save money as well as (20) the earth’s resources.