Please choose correct answer and explain showing work

National savings of a Classical small open economy is 120, Investment is 20, and the net export schedule is: NX = 200 - 50*(real exchange rate). If trade restrictions shift the net export function to NX - 300 - 50*(real exchange rate), in the new situation: O NX rises by 100 and real exchange rate rises by 2 points O NX equals 100, and the real exchange rate rises by 2 points. National Saving rises by 200. Onone of the above