I think the answer is a or b
Explanation:
The conference was held near Yalta in Crimea, Soviet Union, within the Livadia, Yusupov, and Vorontsov Palaces. The aim of the conference was to shape a postwar peace that represented not only a collective security order but also a plan to give self-determination to the liberated peoples of Europe.
answer: Number 2. is either a or b because he faced many challenges during his expedition.
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