Answer:
A is the correct option.
Explanation:
Nationalism can be defined as a movement for promoting the interest of the nation, it aims to gain and maintain a nation's sovereignty. Nationalism accepts that each nation must govern itself without any external interference. Italian unification was also due to the rise of Italian nationalism. The unification is also known as Risorgimento. It was a social and political movement which unifies the different states of the Italian peninsula and formed the kingdom of Italy in the nineteenth century.