The answer is D because you can not be discriminated for things such as race, sexual orientation, or gender this is against the law but D is not because it has nothing to do with the other and if you drink under sge it is against the law
Discrimination is allowed in the case of not being able to drink because you are under age
Explanation:
Discrimination is to treat someone with prejudice or unfairness due to a difference from the other people involved, in the cases A. B. and C we have examples of illegal discrimination that can not be allowed under any circumstances, on the other hand, case D is viable because through that "discrimination" you are in fact protecting the well being of an underage.