The correct answer is A)Italy did not get the territory it deserved after World War I.
The argument that Mussolini makes in this passage is "Italy did not get the territory it deserved after World War I."
Fascist Italian leader Benito Mussolini was angry because Italy had accepted to participate in World War 1, in 1915, when the Entente (the alliance between France, Great Britain, and Russia) promised to gave Italy the control of the territories around its northeastern border such as Tyron. But that did not happen.