Answer:
Slavery and Many travelers lost their way.
Explanation:
The target of The western Expansion was the ex-Louisiana territory that's previously owned by France before being bought by United States.
Many states fight over whether the new western territory should be considered as slaves states (where slavery is allowed) or free states (where slavery is illegal.
On top of that, the navigation technology among settlers were still somewhat primitive. So, when they embarked on a journey from Eastern States to Western states, many of them actually lost their way and ended up settling in Midwest or Southern part of United States.
It seems that you have missed the necessary options that will help us answer this question, but anyway, here is the answer. The area of South America that has been least <span>able to utilize it's resources is COMMUNISM. Communists are known to abhor progress. Hope this is the answer that you are looking for. </span>
B. It can pressures lawmakers to change their opinions on public policy