International trade is most likely to occur when one country needs something it doesn't have, and another country is willing to sell it. Other factors like conflict or tariffs may affect trade but do not drive it as fundamentally as necessity. Understanding these motivations is key to grasping the dynamics of global commerce. ;
International trade occurs when one country needs something it doesn't have, and another country is willing to sell it, primarily driven by economic necessity. Other factors like conflict, market competition, or tariffs may influence trade, but they do not inherently foster it. Therefore, the correct answer is option D.
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