Final answer:
Our need to belong is most clearly threatened by ostracism, which leads to feelings of exclusion and diminishes our sense of social belonging. Other related social science terms include confirmation bias, selective migration, segregation, xenophobia, and the defining feature of a minority group being a lack of power.
Step-by-step explanation:
Our need to belong is most clearly threatened by ostracism. When individuals are excluded or ignored by others, this can lead to feelings of loneliness and a diminished sense of belonging. This is why option c, ostracism, is the correct answer to the question. Cluster migration, drive reduction, unit bias, and refractory periods do not directly threaten our need to belong as much as being actively excluded from social interaction does.
Other concepts related to the social sciences include the worsening of climate change contributing to global refugee crises, the tendency of people to seek information that supports their stereotypes known as confirmation bias, and the idea that people move to areas compatible with their personalities and needs, referred to as selective migration. Also, the least tolerant intergroup relation is segregation, whereas the irrational fear or hatred of another culture is called xenophobia. Lastly, the one defining feature of a minority group is their lack of power, not necessarily their numerical minority or cultural identity.