Dr. Brosnan and Dr. de Waal have eventually found in their study that the monkeys ________.[A] prefer grapes to cucumbers[B] can be taught to exchange things[C] will not be cooperative if feeling cheated[D] are unhappy when separated from others

阅读下述摘要，请简要分析该研究的基本问题、研究思路、主要研究结论以及研究意义。

Title: Perceived Supervisor Support: Contributions to Perceived OrganizationalSupport and Employee Retention Authors: Esenberger, Robert; et al. Journal of Applied Psychology, 2002. Abstract: three studies investigated the relationships among employees' perception of supervisor support( PSS), perceived organizational support( POS),and employee turn over. Study l found,with 314 employees drawn from a variety of organizations, that PSS was positively related to temporal change in POS, suggesting that PSS leads to POS. Study 2 established, with 300 retail sales employees, that the PSS - POS relationship increased with perceived supervisor status in the organization. Study 3found, with 493 retail sales employees, evidence consistent with the view that POS completely mediated a negative relationship between PSS and employee turnover. These studies suggest that supervisors to the extent that they are identified with the organization, contribute to POS and, ultimately, to job retention.