Sociologists tend to define family in terms of

how a given society sanctions the relationships of people who are connected through blood, marriage, or adoption

the connection of bloodlines

the status roles that exist in a family structure

how closely members adhere to social norms

B, connected through blood, marriage or adoption.

Explanation:

Sociologists define a family as an intimate domestic group of people that are related to each other by blood, marriage or adoption and who live under the same roof.

The family is often seen as the main pillar block of a community, it's the place where children learn their first set of values and beliefs and where primary socialization of children takes place.

A family comes into existence when two unrelated people marry or form an emotional relationship. A family connected by blood forms with the birth of the children or with the adoption of them.