Which sentence best completes this diagram?

D. People in the North organize to stop the spread of slavery

Explanation:

The Northern states had acted to abolish slavery in their own states and were against the practice unlike in the South where slavery was considered a way of life. These two wanted to spread their doctrines to the western territories so as to gain more influence.

This is why people in the North organized to stop the spread of slavery when the South wanted to spread it to the west leading to a very politically divided nation that would eventually go to war.

b. second continental congress

lincoln presided over the union victory in the american civil war, which dominated his presidency. a former whig, lincoln ran on a political platform opposed to the expansion of slavery in the territories. his election served as the immediate impetus for the outbreak of the american civil war.