Final answer:
A person with a family history of alcoholism has the highest risk among the options provided, because genetic predisposition is a significant risk factor for developing alcoholism.
Step-by-step explanation:
Based on statistics associated with risk factors for developing alcoholism, a person with a family history of alcoholism is at the greatest risk. This is due to the strong genetic component linked to alcohol dependency. Family history is a well-established risk factor in the development of alcoholism, increasing the likelihood of an individual developing similar problems. Despite other risk factors such as social isolation, depression, and stress, which indeed can affect a person's alcohol consumption, the genetic predisposition plays a more fundamental role when evaluating risk for alcoholism.