Can some plz help meh? Someone

a decrease in cotton production on southern platforms

Explanation: step by step

i think the anwser is A but i not full sure so if you get it worng please let me know what the anwser was :  ) :  )

Explanation:

as general terms,  indian territory,  the indian territories, or  indian country  describe an evolving land area set aside by the  united states government  for the relocation of  native americans  who held  aboriginal title  to their land. in general, the tribes ceded land they occupied in exchange for  land grants  in 1803. the concept of an indian territory was an outcome of the 18th- and 19th-century policy of  indian removal. after the  civil war(1861–1865), the policy of the government was one of  assimilation.