What is a reason that the missouri compromise did not have lasting effects?

A. It only applied to the lands of the Louisiana Purchase
B. It only applied to the lands of the Mexican Cession
C. It relied on popular sovereignty
D. It limited the number of states that could be admitted per year

The Free- Soil Party would most likely agree with which of the following?
A. plantation system
B. manifest destiny
C. increased immigration
D. popular sovereignty

1. D?
2. C?

I'm not sure. I would appreciate any help.