(a) A claimant may assert a claim in a specified foreign money. If a foreign money is not asserted, the claimant makes a claim for a judgment in United States dollars.
(b) An opposing party may allege and prove that the claim is, in whole or in part, for a different money than that asserted by the claimant.
(c) Any party may assert a defense set-off, recoupment, or counterclaim in any money without regard to the money of other claims.
(d) The determination of the proper money of the claim is a question of law.