How Do You Know That a Group in Which You're

How do you know that a group in which you're taking part is suffering from groupthink?

A) Peer pressure makes you agree with the ideas of the other people in your group.
B) Minority dissent is allowed,even encouraged.
C) All ideas and conclusions must be backed up with data.
D) The group would rather take the time to come to the right decision rather than agree too quickly on what may be the wrong decision.
E) The group actively considers new ideas,even if these ideas challenge underlying assumptions.