Final answer:
Giovanni Giolitti's selection by Crispi on the specified date cannot be confirmed, but Italian unification was significantly advanced by Cavour and supported by Garibaldi's Red Shirts in the south.
Step-by-step explanation:
The question pertains to the Italian statesman Giovanni Giolitti. However, the date and context provided seem to be incorrect as Giolitti was not selected for a role by Crispi on March 9th, 1889. Instead, it's significant to note that Camillo di Cavour was a key figure in the unification of Italy. He was appointed Prime Minister in 1852 and led the push for unification by forming an army and an alliance with the French emperor Napoleon III. They defeated the Austrian Empire in 1859, leading to the cession of Lombardy and subsequent unification efforts. Giuseppe Garibaldi and his Red Shirts played a crucial role in the south by aiding the revolution on Sicily.