Why was camillo di cavour important to the italian unification

Count Camillo di Cavour became prime minister of the Kingdom of Sardinia In 1852 . It was his leadership and accommodating policies that led to the unification of Italy in little more than a decade.
Cavour was able to persuade Napoleon to a secretly planned war against Austria. By early 1859, Cavour had caused a crisis that provoked the Austrians to send an ultimatum demanding Piedmontese disarmament. As part of the "plan", Cavour rejected the ultimatum which led to the subsequent war with the Austrians. The French came to the aid of the Piedmontese and the Austrians were defeated in the two major battles of Magenta and Solferino. The Austrians were forced to surrender Lombardy, with its great city of Milan (my home town), to Napoleon III. Finally, in 1859, Napoleon transferred Lombardy to the sovereignty of Victor Emmanuel II.
Following elections during 1859 and 1860, all northern states (of the Italian peninsula), except Venetia, which was still part of Austria, joined the Kingdom of Sardinia. Napoleon's growing concern with respect to the sudden (large) size of his neighbor was resolved in part by the cessation of the Sardinian provinces of Savoy, near the Alps, and Nice, on the Mediterranean coast to France in 1860 . After 1860, the only French presence on the Italian peninsula was in the city of Rome, where French troops remained at the request of the pope.

The answer is option c.