The correct answer is A. Count di Cavour was a cunning prime minister who played a major role in the unification of Italy.
He was minister of the Kingdom of Sardinia from 1850 to 1852, president of the Council of Ministers from 1852 to 1859 and from 1860 to 1861. In the same 1861, with the proclamation of the Kingdom of Italy, he became the first president of the Council of Ministers of the new State and died in that post.
Although he did not have a preordained plan of national unity, he succeeded in managing political events (riots in the Grand Duchy of Tuscany, in the duchies of Modena and Parma and in the Kingdom of the Two Sicilies) which together with the Enterprise of the Thousand led to the formation of the Kingdom of Italy.