Question: The leader that requested the Marble Arch in Libya to be built was the "heir apparent" of what dictator?
Sentence (from "Italo Balbo"): Italo Balbo (Ferrara, 6 June 1896 – Tobruk, 28 June 1940) was an Italian Blackshirt ("Camicie Nere", or CCNN) leader who served as Italy's Marshal of the Air Force ("Maresciallo dell'Aria"), Governor-General of Libya, Commander-in-Chief of Italian North Africa ("Africa Settentrionale Italiana", or ASI), and the "heir apparent" to Italian dictator Benito Mussolini.
Relevant evidence: Yes