资料：The personal computer was a revolution in information technology that spawned a $50 billion hardware business, with another $30 billion in software and peripherals （eg. mouse, keyboard, printer, etc.） by 1991. During its short 15 years, the industry evolved through three successive periods. During its first 5 to 6 years, it was characterized by explosive growth and multiple, small competitors vying for a piece of the market. From 1981 to 1985, the industry became a battle for standards and retail shelf space. The third era was one of increasing fragmentation. From 1986 through 1991-1992, new manufacturers from around the world grabbed from the industry leaders as new channels of distribution emerged and product innovation as well as revenue growth slowed.
During the early years of the industry, venture capital in the U.S. encouraged the entry of new firms that offered products in every conceivable shape and size. By 1980, new entrants flooded the market, prompting distinct standards and unique technical features. Almost every firm had a different configuration of hardware and software. The first PC had relatively little speed or memory. However, even these early computers allowed managers to perform tasks that were very time consuming.
When did the PC industry start?
本题考查的是细节理解。
【关键词】When；PC industry；start
【主题句】第1自然段The personal computer was a revolution in information technology that spawned a $50 billion hardware business, with another $30 billion in software and peripherals （eg. mouse, keyboard, printer, etc.） by 1991. During its short 15 years, the industry evolved through three successive periods.个人电脑是一场信息技术革命，截止到1991年，它催生了价值500亿美元的硬件业务，300亿美元的软件和周边设备（如：鼠标，键盘，打印机等等）。在短短的15年里，该行业依次经历了三个时期。
【解析】本题的问题是“个人计算机产业什么时候开始？”。选项A意为“1981年左右”；选项B意为“1986年左右”；选项C意为“1976年左右”；选项D意为“ 1992年左右”。根据文意，1991-15=1976，故选C。
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