21)Which of the following statements is true regarding the effect of group cohesiveness and 21) performance norms on group productivity? ' A) The productivity of the group is affected by the performance norms but not by the cohesiveness of the group. B)When both cohesiveness and performance norms are high, productivity will be high. C) If cohesiveness is low and performance norms are high, productivity will be low D) When cohesiveness is low and performance norms are also low, productivity will be high. E)If cohesiveness is high and performance norms are low, productivity will be high