La Salle is best known for __________.

René-Robert Cavelier, Sieur de La Salle, traveled down the Mississippi River to its mouth in 1682 and claimed the surrounding territory for France, naming it Louisiana. This makes choice C, “traveling the length of the Mississippi River and claiming it for France,” the best answer. The first successful French settlement in North America was founded by Samuel de Champlain at Quebec, not La Salle.

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