An elderly man who lives with his adult son was diagnosed a year ago with early-stage Alzheimer's ...

An elderly man who lives with his adult son was diagnosed a year ago
  with early-stage Alzheimer's disease. The physician never discussed
  alcohol. The man gets angry when the son discusses his condition, and
  he drinks.
 
  The father drank all his life, but neither man considered it a
  problem. What does this information suggest?
  A. The man has a co-occurrence of Alzheimer's disease and
  alcoholism.
  B. The man very likely has an AUD and alcohol-related dementia.
  C. The man is at risk for an AUD but probably does not have one.
  D. The son is in denial about his father's alcoholism.