-Money-
so they can continue to expand
-Resources-
to fuel the empire they are building
-Power-
To rule what they have and increase the influence of their religion and ideals.
I believe the answer you are looking for is A.
One item can be the weapons. Many Europeans gave the natives a bunch of weapons because they had plenty. They even gave them faulty weapons or broken ones because the natives didn't know any better.
This is true. The battle of Palmito Ranch occurred from May 12, 1865 to May 13, 1865 while the Civil War ended on May 9, 1865.
Hope this helps!
