Answer: a) selecting an impartial leader.
Explanation:
Groupthink is the technique which is used by a group of people to make a decision without considering opinion, thoughts,suggestion etc of members of group.This leads to elimination of creativity and degraded decisions.
To eliminate group-think, the possible way is to choose a impartial leader of that group. Impartial leader will tend to welcome and hear opinion and suggestion from members and also will not expect that everyone should to think about particular result.
Other options are incorrect because people who raise objection are also required so that their objection can be considered for betterment of decision.Conformity cannot help in removing group think.Outside experts are already not a part of group.
Thus, the correct option is option(a).
