Answer:
Was finally achieved by militaristic Prussian politicians
Step-by-step explanation:
First, Klemens von Metternich resigned in 1848, before any attempt of unification. And second, the Frankfurt Assembly failed to propose an economic/political structure for the unification. So, the efforts were led by Prussia, at that time one of the major German states. When the king William IV from Prussia died, his brother ascended the throne, and with him, Otto von Bismarck, a conservatory leader from the Army. From that moment, Bismarck and the Prussian politicians would lead to unification.