Which of the Following Is Predicted by the Self-Categorization Explanation

Which of the following is predicted by the self-categorization explanation of group polarization?

A) Polarization should be greater for in-groups than for out-groups.
B) Polarization should be greater after more group discussion.
C) Polarization should be greater for risky than for cautious decisions.
D) Polarization should be greater when there is initial disagreement among the group members.