Which of the Following Steps Can Be Taken by a Manager

Which of the following steps can be taken by a manager so as to minimize groupthink?

A) Increase the group size.
B) Encourage group leaders to express their own opinions especially in the early stages of deliberation.
C) Prevent all team members from playing the role of "devil's advocate."
D) Ask the group members to first focus on the positives of an alternative rather than the negatives.
E) Ask the group leader to actively seek input from all members.