Why Did Free Navigation of the Mississippi River and the Right

Why did free navigation of the Mississippi River and the right of deposit in New Orleans matter to American farmers and merchants living in the trans-Appalachian West during the early 1800s?

A) American settlers in the trans-Appalachian West depended on access to the Mississippi River and New Orleans for their economic survival and prosperity.
B) The Mississippi River and New Orleans served as sources of defense against hostile Indian tribes living in the trans-Appalachian West.
C) The British boycott of American-manufactured goods meant that settlers in the trans-Appalachian West had no other choice but to sell their products to the Spanish in New Orleans.
D) Trans-Appalachian farmers and merchants avoided costlier taxes imposed by the U.S. government by transporting their goods down the Mississippi River and selling them to Spanish merchants in New Orleans.