The correct answer is option (c) Count Cavour.

Count Camillo Benso di Cavour, commonly known as Count Cavour, was a key figure in the unification of Italy. He played a crucial role in the political and diplomatic efforts that led to the formation of a unified Italian state in the 19th century.

Below are the key points explaining why Count Cavour is considered the Prophet of the unification of Italy:

1. Background:
- In the early 19th century, Italy was divided into several independent states, including the Kingdom of Sardinia, the Papal States, and various duchies and kingdoms.
- Count Cavour, as the Prime Minister of the Kingdom of Sardinia, aimed to unite these separate states into a cohesive Italian nation.

2. Diplomatic and Political Efforts:
- Count Cavour initiated a series of diplomatic maneuvers and political reforms to achieve his goal.
- He modernized the economy and infrastructure of Sardinia, promoting industrialization and trade.
- He implemented liberal reforms, such as freedom of the press and the establishment of a constitutional government, to gain support from the people.

3. Alliance with France:
- Count Cavour recognized the importance of international support for the unification cause.
- He formed an alliance with France, led by Emperor Napoleon III, in the hopes of using French military power to defeat the Austrian Empire, which controlled several Italian territories.
- The alliance resulted in the Second Italian War of Independence in 1859, in which France and Sardinia fought against Austria.

4. Expansion of Sardinia:
- Through strategic diplomacy and military victories, Count Cavour expanded the Kingdom of Sardinia's territory.
- He acquired territories such as Lombardy, Parma, Modena, and Tuscany, gradually expanding the influence of Sardinia across northern Italy.

5. Role in the Unification:
- Count Cavour's efforts laid the foundation for the subsequent unification of Italy.
- His diplomatic skills, political reforms, and alliance with France created favorable conditions for further unification efforts led by Giuseppe Garibaldi and King Victor Emmanuel II.
- The Kingdom of Italy was proclaimed in 1861, with Victor Emmanuel II as its king, and Cavour as one of its key architects.

In conclusion, Count Cavour is considered the Prophet of the unification of Italy due to his instrumental role in laying the groundwork for Italian unification. His diplomatic maneuvers, political reforms, and alliance with France were crucial in bringing about the formation of a unified Italian state.