Alcohol just never seemed to be an intoxicating substance for him . He could drink extensively , the strongest liquor available ( and in fact his chosen beverage was Absinthe ) , but still remain completely sober . Marijuana acted much like an energy drink would to someone else .

Question: Why is their friend able to drink so much ?
Answer: They always smoke marijuana while they drink .They are used to drinking a lot of alcohol .They are a large person .None of the above choices .