Between classes, you notice how smokers congregate outside the doors of the building. When interacting with one another, they seem to behave as if they identify as quite different from the non-smokers who happen to be outside the door. What term would best describe the group of smokers?

A. an ingroup
B. an outgroup
C. a clan
D. an ethnocengroup

Explanation:

In Psychology an ingroup is defined as the group of those people who share same particular qualities

In the given example, there are two group of people -smokers and non smokers

Smokers will share their smoking quality with other smokers whereas non smokers will share their non smoking quality with other non smokers  

So smokers in this case will represent an ingroup

An outgroup does not share the same particular qualities hence smokers will be an outgroup for non smokers and vice versa

A clan is defined as group of families that have common ancestry whereas an ethnic group includes those who share same cultural background

the alkaline earth metals (beryllium (be), magnesium (mg), calcium (ca), strontium (sr), barium (ba), and radium (ra)) are a group of chemical elements in the s-block of the periodic table with very similar properties: shiny. silvery-white. hopefully this ? i didn't fully understand the question