Answer:
B. Jefferson believed that securing lands to the West Coast would allow the U.S. to secure a port in New Orleans to export American goods abroad.
Step-by-step explanation:
Whoever bought it would be either an enemy or an ally America could not risk someone controlling there main trade route so they were forced to buy it. Atleast that was Jeffersons point of view. This also would double the size of the U.S. and allow more trade to be apparent.
~ LadyBrainiac