Hello!
Social interactions may help lower the risk of Alzheimer's disease by the brain constantly working behind the scenes.
So like 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 ''by helping keep a person's mind active'' is the correct answer.
Toodles~
