Why Did Klemens Von Metternich, as Austrian Foreign Minister, Have

Why did Klemens von Metternich, as Austrian foreign minister, have to oppose the spread of nationalism in Europe?

A) As a classical liberal, he feared that it would lead to intolerance and violence.
B) Austria's rulers feared the power of a resurgent nationalist Ottoman Empire.
C) Austria pursued a policy of free trade, which was incompatible with economic nationalism.
D) Austria was a multiethnic empire, and the spread of nationalism among its different ethnic groups threatened to dissolve the empire.