Answer:
C. Punish nations for disobeying international law.
Step-by-step explanation:
Economic sanctions are and have been used to punish nations for disobeying international law. A prime example of this is in the current Russia and Ukraine conflict, where many nations worldwide have united to impose multilateral sanctions on Russia. These sanctions include removal from SWIFT, various bans on Russia's oil imports, and sanctions applied to an extensive list of oligarchs. All of this is to condemn the attack on Ukraine which is viewed largely as immoral and unjust.
In the past, economic sanctions have also been used due to violations of international laws. South Africa was sanctioned over apartheid, China over human rights violations, and North Korea (DPRK) over their development of weapons of mass destruction. An outlier or exception in history would be the US imposing sanctions on Cuba, but this was unilateral. This was due to the US disagreeing with their political alignment with Communist powers, (the Soviet Union) not because Cuba broke international law. (they didn't) The reason Cuba was sanctioned was more because of the Cold War tensions, US political culture, and state factors that made it imperative for presidents to show that they were "tough on communism."
Apart from the outlier, all these instances, although most unsuccessful, do show sanctions being used to punish nations with economic consequences for violations of international law.
We can also go ahead and evaluate why the other answer choices are not as good
Option A: protect domestic industries from international competitors.
This is incorrect because the protection of domestic industries wouldn't be done most effectively by sanctions, rather high tariffs to discourage imports from international competitors and drive the prices of imported goods up. Sanctions often do harm domestic industries because they often hurt the country sanctioning the other as well- especially in the case of Russia and China considering how significant those economies are. Sanctions can easily cause a disruption in the supply chain via shortages of commodities, and this harms domestic industries.
Option B: help domestic industries gain more business.
When digging into the economics behind this, it makes little sense. By sanctioning a country, not only are supply chains disrupted, but the sanctioning country is often prohibiting its exports from reaching the sanctioned country. This actually decreases business for the domestic industries by taking away valuable consumers. While it may create higher domestic demand due to a lack of imports, this still is not the most logical choice.
Option D: encourage nations to give up their nuclear weapons.
While sanctions were imposed on North Korea in history due to concerns with their development of nuclear weapons and anti-ballistic missiles, this reason is too specific. Rather, the development of these weapons also falls under violations of international law, and hence the broader choice that can encompass more examples rather than just one would be a better answer choice for this question.