The correct answer is C. He wanted to buy New Orleans and saw the opportunity to greatly expand the nation.
Jefferson saw the need to acquire New Orleans because of his fear that France would use this city as a point of support to press militarily on the American Union.
In 1763, by the treaty of Paris, France had ceded to England a part of Louisiana territory west of the Mississippi River (In the hands of the Union since its Independence) and the rest of the Louisiana Territory had ratified its cession to Spain. When Napoleon took power in France, he took control of New Orleans and in 1800 he made two actions (he took New Orleans as a base for military operations in the face of revolts in Haiti and Santo Domingo and the impediment of storing merchandise to the Americans) that Jefferson considered as a threat to national sovereignty and a risk to the Napoleonic advance.
This led him to establish negotiations to buy New Orleans from France. France initially refused but in 1803 the conditions had changed and Napoleon decided to abandon his pretensions in America and decided to concentrate his expansionist efforts in Europe, therefore he sold the entire territory of Louisiana to the American Union for a really low number.
Jefferson achieved the goal of buying New Orleans and his expectations were expanded, since from this acquisition he took courage to undertake expeditions in order to further increase the national territory.
The Congress gave a tough debate on this issue but ended up supporting the expansionist strategy of Jefferson.
