Producers of the Beta format for video-cassette recorders （VCR`s）， for example， were first to develop the VCR commercially in 1975，but producers of the rival VHS（Video Home System）format proved to be more successful at forming strategic alliances with other producers and distributors to manufacture and market their VCR format. Seeking to maintain exclusive control over VCR distribution， Beta producers were reluctant to form such alliances and eventually lost ground to VHS in the competition for the global VCR market.

　　Despite Beta`s substantial technological head start and the fact that VHS was neither technically better nor cheaper than Beta， developers of VHS quickly turned a slight early lead in sales into a dominant position. Strategic alignments with producers of prerecorded tapes reinforced the VHS advantage. The perception among consumers that prerecorded tapes were more available in VHS format further expanded VHS`s share of the market. By the end of the 1980`s， Beta was no longer in production.

　　1.The passage is primarily concerned with which of the following？

　　（A） Evaluating two competing technologies

　　（B） Tracing the impact of a new technology by narrating a sequence of events

　　（C） Reinterpreting an event from contemporary business history

　　（D） illustrating a business strategy by means of a case history

　　（E） Proposing an innovative approach to business planning

　　2. According to the passage， today's successful firms， unlike successful firms in the past， may earn the greatest profits by

　　（A） investing in research to produce cheaper versions of existing technology

　　（B） being the first to market a competing technology

　　（C） adapting rapidly to a technological standard previously set by a competing firm

　　（D） establishing technological leadership in order to shape product definitions in advance of completion firms

　　（E） emphasizing the development of methods for the mass production and distribution of a new technology

　　3.According to the passage， consumers began to develop a preference for VCR`s in the VHS format because they believe which of the following？

　　（A） VCR`s in the VHS format were technically better than competing-format VCR`S.

　　（B） VCR`s in the VHS format were less expensive than competing-format VCR`S.

　　（C） VHS was the first standard format for VCR`s.

　　（D） VHS prerecorded videotapes were more available than Beta-format tapes.

　　（E） VCR`s in the Beta-form would soon cease to be produced.

　　4. The author implies that one way that VHS producers won control over the VCR marker was by

　　（A） carefully restricting access to VCR technology

　　（B） giving up a slight early lead in VCR sales in order to improve long-term prospects

　　（C） retaining a strict monopoly on the production of prerecorded videotapes

　　（D） sharing control of the marketing of VHS-format VCR's

　　（E） sacrificing technological superiority over Beta format VCR's in order to remain competitive in price