Meriwether lewis and william clark were: a. explorers sent by jefferson to study nature and geography. b. negotiators sent by jefferson to buy territory from france. c. leaders of american forces at the battle of fallen timbers. d. the first and second governors of the northwest territory.

A.explorers sent by Jefferson to study nature and geography.

Explanation:

Meriwether Lewis and William Clark were explorers sent by Jefferson to study nature and geography. 

It happens to be a very important expedition that used up to two full years before it was completed. In this period of time, they explored the western region of the United States. Their main aim and objective was to form a comprehensive map of those regions, which also includes studying of the geography and wildlife, majorly concentrating on the state of Louisiana, in particular.

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strong-mayor system