Group leaders should refrain from expressing strong opinions at the beginning of discussions. leaders should also encourage their teams to consider alternative ideas and treat dissenters respectfully.

in this way, leaders can prevent which of the following from happening?
a. conformity
b. deindividuation
c. risky-shift effect
d. groupthink

D. Groupthink.

Explanation:

In a group discussion, people keep their opinions, ideas and thoughts forward. But sometimes all individual of the group do not agree on a certain conclusion. So instead of speaking up and creating a conflict these individual keep quiet. Such phenomenon of accepting the view of the group despite having different opinions is called groupthink.

In the given case, the leader is refraining to give strong opinions and encouraging them to respectfully engage in the discussion. So, he is preventing groupthink by doing this because he is involving all members to participate and share their opinions so that they can view the situation from all perspectives.

So, the correct answer is option D.