Answer:
The correct answer is D. The political party that was formed to oppose the spread of slavery was the Republican Party.
Step-by-step explanation:
On March 20, 1854, the Republican Party was founded. Most of the founding members of the Republican Party had been members of the Whig Party of the United States, but some were former members of the Democratic Party, and another part were independent or had been part of other groups (such as the Free Soil Party).
What all these groups had in common to form the new party was their ideological belonging to the powerful anti-slavery or abolitionist movement, which brought together all white-skinned people in the Northern States of the United States who were fighting to abolish slavery of black people in the southern states of the country.