Answer: A. Several publications in the mid 1800s made the cruelties of slavery public in the north.
The Missouri Compromise of 1820, which allowed Missouri to become a slave state, further increased anti-slave sentiment in the Northern states. The abolitionist movement began as a more organized, radical and immediate attempt to end slavery than earlier movements.
Its fair to say that "it is designed to bend like a willow" because the constitution was made fairly flexible, and this gave the government bandwidth to extend its power to meet new situations.
Conference committees operate after the House and the Senate have passed different versions of a bill. Conference committees exist to draft a compromise bill that both houses can accept. Both houses of Congress must eventually pass identical legislation for the bill to be presented to the President.
When a country establishes foreign policies, the interest of the country itself (A) is the most prioritized interest in constructing foreign policy. This is logical given that a country creates a strategy for foreign policy and national security based upon representing their own peoples interests first.