![](https://cos-cdn.shuashuati.com/pipixue-web/2020-1231-2005-12/ti_inject-812ce.png)
What does the lecture mainly discuss?
A.
An advantage of making unanimous decisions in groups
B.
A study related to the concept of groupthink
C.
The history of research on group decision making
D.
The amount of time required for a group to solve a problem