(A) ** The heir of the throne of Austria-Hungary
(B) The future of Tsar of Russia
(C) The leader of germany air-force
(D) The leader of the french government
EXPLANATIONS BELOW
Concept note-1: -Franz Ferdinand was the eldest son of Archduke Karl Ludwig of Austria, the younger brother of Emperor Franz Joseph I of Austria. Following the death of Crown Prince Rudolf in 1889 and the death of Karl Ludwig in 1896, Franz Ferdinand became the heir presumptive to the Austro-Hungarian throne.