4. which development signaled that some portions of the country were unwilling to accept the results of the 1860 presidential election?

The elections of 1860 made Lincoln the president and this led to more tensions in the north and south part of the United States leading to civil war.  

Explanation:

The elections of 1860 was won by the republican party in the United States and Lincoln came to power as the president of the United States and this was not liked by the south part.

Because they did not like Abraham to come in power because he did not interfere in the problem of slavery in the southern states and this made the people of south go against him. Although Lincoln was against slavery in the whole country but did nothing for the south.