What was Thomas Jefferson’s greatest contribution to westward expansion and how did it affect the US

Thomas Jefferson acquired an interest in western exploration early in life. ... While president, Jefferson successfully acquired the Louisiana Territory from France in 1803 and sent the Lewis and Clark Expedition (1803–1806) on a mapping and scientific exploration up the Missouri River to the Pacific.

That westward expansion was greatly aided by the completion of the Transcontinental Railroad in 1869, and passage of the Homestead Act in 1862.

In the mid-19th century, the quest for control of the West led to the annexation of Texas and the Mexican–American War. ... This expansion led to debates about the fate of slavery in the West, increasing tensions between the North and South that ultimately led to the collapse of American democracy and a brutal civil war.

Explanation:

        i'm fairly sure that the correct answers are 2 and 3.

        i used both my knowledge of world history and the process of elimination to obtain these answers. option 1 cannot be a possible selection because the mandate of heaven belongs to ancient chinese philosophical belief. option 4 sounds like it would benefit the region than detriment it. however, both 2 and 3 explain a potential reason for what could have contributed to the fall of the roman empire.

      hope this ! if i were you, i'd get a second opinion, because i haven't taken this course for a year. best of luck!

***websites that me understand the curriculum better last year are and ***

sam houston basically made tx he fought for anrew lead troops in the battle of san jacinto and then became president and james polk