题目

Today’s workplace is unique in history. Never before have we seen people working together who represent such different backgrounds and experiences. This difference of age, race, gender, and work style makes it very difficult to organize and run a company. As a result, companies are looking for individuals who can manage a wide range of employees effectively. Increasingly, managers are discovering that age differences among workers are a major cause of concern. This has been an important realization. The management difficulties and challenges have led some experts to study intergener在等差数列{an} 中，a3+a5+2a10=8，则此数列的前13项的和等于   [     ]A．8B．13C．16D．26