A．
To achieve a certain goal, a combination of three or more interacting and interdependent individuals
B.
Interdependence：The mutual dependence of group members on one another.
Common Goal：The driving force that brings people together to form is a common goal.
Group Personality：When people come together in a group, they form a collective identity that becomes the group personality.
Commitment：Commitment is the desire of group members to work together to complete their task to the satisfaction of the entire group.
Cohesiveness：Cohesiveness, an extension of commitment, is the attraction that group members feel for each other and their willingness to stick together
Group Conflict：The truth of the matter is that whenever people come together in any communicative context there is bound to be conflict of some sort. Conflict does not always have to be harmful. Conflict can be productive and can result in better decisions and solutions to problems.
Social Facilitation：The tendency for a person to release energy that would not be released if the individual were acting alone is called social facilitation
Gender Differences：Research shows that groups consisting of both men and women are more likely to be dominated by men talking than by women talking. When groups are in competition with one another, it appears that women are more cooperative with their opponents than are men. When groups are small in size, women prefer to work with other women, while men don’t have a gender preference. It is much more difficult to achieve cohesiveness in all-male groups than in mixed-gender groups or all-female groups
Group Size： A group that is too small may limit the information and ideas that are generated, while a group that is too large may limit the contribution that each person can make. The larger group, the greater the variety of skills and information possessed by its members
Norms：Norms are the expected and shared ways in which group members behave.
For a group to function effectively, its members must agree on how things are to be done.
Norms also help give a group structure.
C.
Relevance：Members’ comments should pertain to the topic and goals of the discussion at hand and should deviate only when tension needs to be released.
Relatedness：The goal of relatedness is to make sure that contributions tie in with what has been said before and what is apt to be said next.
Timeliness：To give more impact to a good idea you should, introduce it at a favorable time so that it gets the group’s full attention and consideration.
Sufficient Length：Choosing the best length for a comment requires good judgment. The goal is to make sure that the comment you contribute is long enough to make your point.
Clarity：Always remember that meanings are in people, not in words. Thus, you cannot assume that everyone in the group will understand your idea in the same way that you do.To avoid misunderstandings, define your terms and provide examples to ensure a common ground.
Informativeness：Make sure that your statement are accurate and objective. This requires having a good understanding of the topic and doing prior research. Cite source of information when appropriate, and select sources that are not biased.
Openness to evaluation：Group discussion can lead to the best possible information and the best possible decision, but this will happen only if members open their comments to evaluation. Criticism should not be ignored or avoided. At the same time, members must remember that evaluation can be constructive only when they focus on the contribution and not on the person.
Provocativeness：Comments should be made not only to bring the group closer to its goal, but also to fuel thought for further contributions. Lack of time should never be the sole reason for closing off discussion if an idea has not been fully discussed and evaluated.Asking questions, challenging ideas, and disagreeing can be valuable contributions as long as their goal is to make the final group product the best one possible.