Two people who have chosen to be friends for over 30 years is an example of a group that is both primary and voluntary.
Answer: Option B
Step-by-step explanation:
Primary groups are the groups which have most importance in our lives. The people who are a part of this group are the closest to us and are our friends and families.
The voluntary groups are the groups which we form on our wish and will and not have been given to us without our wish. So the friend who has been in our life for more than thirty years is one of the most important people of our life and has huge emotional importance for us.