The areas that sociologists investigate are parts of our everyday lives. Sociologists talk about families, groups, politics, economy, factories, religion, authority, etc. However, sociologists live in the society they investigate, they have families, they work in the work places, they are a part of the economy. They cannot completely isolate themselves from the society. What people say and do is the basis of the research subject of sociology. Nevertheless, there are important differences between commonsense and sociology. Thus, B is the correct answer.