Which of these is the strongest example of multilateral foreign policy?

one nation states publicly that it will refuse to trade with any nation that criticizes its leader.
one nation refuses to trade with a rival nation because it does not allow women to vote in an upcoming election.
two rival nations go to war with one another over disputed territory.
two allied nations enforce economic sanctions on a country until its government changes a key policy.

Why would a person who believes in a strict interpretation of the constitution have a concern with the elastic clause? a) the elastic clause limits the ability of the government to respond to new needs of the nation. b) the elastic clause gives the supreme court original jurisdiction in a limited number of cases. c) the elastic clause allows congress to exercise powers not specifically listed in the constitution. d) the elastic clause guarantees that a citizen's property cannot be taken away with due process of law.