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IV. Choose A, B, C, or D to indicate the option that is the best answer to each of the gaps.

In Western countries, electricity, gas, and water (21) …………………. not luxuries but necessities. Companies now realize that consumers want products that will not only work effectively, (22) …………………. also save money.

For most North American households, lighting accounts for 10 percent to 15 percent of the electricity bill. (23) …………………., this amount can be reduced by replacing an ordinary 100-watt light bulb with an energy-saving bulb. These bulbs use a quarter of the electricity of standard bulb and last eight times longer. Therefore consumers can (24) …………………. about US$7 to US$21 per bulb.

In Europe, there is a labeling scheme for refrigerator, freezers, washing machines and tumble dryers. The label tells the consumers (25) …………………. energy efficiency each model has, compared with other appliances in the same category.

21. A. is                B. were                 C. was                            D. are

22. A. and           B. as                    C. so                              D. but

23. A. However   B. Even though    C. Although                   D. Therefore

24. A. pay             B. consist              C. save                           D. make

25. A. how much  B. how many        C. how                           D. what