Answer:
D. Limits were set about where slavery could spread in U.S. territories
Explanation:
In return to the limits of where slavery can spread, the US upheld that they will remain strict in catching and returning slaves, much to the displeasure of abolitionists in the North.
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Answer: The upper house has more decision then but it can be overruled
Explanation: What are you trying to say
The Executive branch must receive approval from "the Senate" when appointing heads of executive departments, ambassadors, and Federal Court Judges, since this is one of the most important examples of the system of "checks and balances" that exists in the US.