Apresentation by a study group on a selected topic is a type of discussion.

Is a type of discussion called small group discussion

Explanation:

A small group discussion is usually followed by a presentation of the selected topic that was discussed within the group usually a small group of scholars working on project topic or homework.

A small group discussion can also hold between a board of Engineers or project supervisors which ultimately leads to a presentation after discussion to the relevant audience whose duties are to receive the results of the discussions made. A presentation is usually a piece of information been passed to the relevant audience in a formal way like lecturing or through a speech.

norsemen from northern countries had made earlier journeys