The reason why small teams perform better than large ones is because of the first option, members exchange more opinions, it is because in large groups, there are a lot of people in the group which is hard to communicate and to exchange more opinions as the group is large and could cause misunderstanding. But when in small groups, it is much easier to exchange opinions as they are only small in size, making it easier to communicate and to understand each other compared to a large group who are comprised of many individuals, causing unclear conversations and misunderstandings when not handled properly. Other options does not correspond to the question as it does not explain why small teams perform better than large groups.
