A challenge that Italy faced after unification was too much control by the church.
ongoing wars with other nations.
political unrest and instability.
demand for new nation-states.

political unrest and instability.

Explanation:

The Italian unification was the process that the country faced in the 19th century that united the different kingdoms that existed in the peninsule of Italy and created the Italian Empire, this was difficult, as any unification of former empires into a new one would be because they had political unrest and instability, imagine different former kings trying to gain control over the new kingdom while at the same time losing their own, all the people losing their identity trying to find a new one, and trying to let go of the previous wars the had with eachother.

C) to abolish the practice of slavery within the United States.