How might social interactions lower the risk of alzheimer's disease?
by a person remember things
by keep a person's mind active
by a person feel young
by a person stay in touch with reality

Social interactions may help lower the risk of Alzheimer's disease by the brain constantly working behind the scenes. When a person is socially interacting, they are using their mind even if they don't notice. Someone in the beginning stages of Alzheimer's will not remember a lot of details about their lives. However, socially interacting may be able to bring back memories that will trigger the brain to remember the details they had forgotten. So B is the correct answer.