Which of the following is a power officially granted to the United Nations?

The UN does not have the authority to approve the constitutions of newly formed governments. Instead, it supports member states in developing governance frameworks through advisory assistance and guidance, but it does not intervene in domestic constitutional affairs or grant approvals.

While the UN can facilitate discussions on trade and promote fair practices through its various bodies, it does not have the explicit power to regulate trade among nation-states. Trade regulation typically falls under the jurisdiction of individual countries or specific organizations like the World Trade Organization (WTO).

The UN does not control international migration. Instead, it addresses migration issues through specialized agencies like the International Organization for Migration (IOM) and promotes cooperative frameworks for managing migration, but national governments retain control over their borders and immigration policies.