In short, some countries were not benefited in the trade sector
The main reason as to why the southern planters has opposed to the wilmot proviso was because of the reason that if they don't oppose to it, it would likely abolish slavery in terms of the lands that they have gained from the Mexican American War.
Answer:
d
Explanation:
I read about this recently
I think the answer is D. France.
But I am not sure.
The answer is D!
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