Which of the following is NOT a strategy to prevent groupthink?

To counteract or prevent groupthink, several strategies can be employed:

1. Encouraging and rewarding critical thinking and disagreement among group members.
2. Promoting the presentation of alternative courses of action within the group.
3. Seeking evaluation and input from external experts to assess the group's decisions.
4. Encouraging group members to seek feedback from trusted individuals outside the immediate group.