Final answer:
The European nation with the strongest military during the age of imperialism was the United Kingdom, who had naval superiority essential for its global empire.
Step-by-step explanation:
During the age of imperialism, the European nation with the strongest military was the United Kingdom (c). The United Kingdom had the most powerful navy in the world, which was crucial for protecting its vast overseas empire and trade routes. Its naval dominance, reinforced by the notion that 'Britannia rules the waves,' allowed for the control of vital sea lanes and the ability to quickly deploy military forces across the globe.
Germany's military might rapidly grew, particularly their navy under Kaiser Wilhelm II, as they entered into a naval arms race with Britain; however, the UK maintained its edge going into World War I.
Additionally, the Triple Entente, an alliance between the UK, France, and Russia, represented a significant portion of European military power.
As a refresher, the Triple Entente consisted of Britain, France, and Russia and was part of the entangled alliance systems that existed on the eve of the First World War. Germany, while a formidable military power, especially after its unification and successful display of strength in the Franco-Prussian War, did not outnumber or outmatch the combined forces of the Triple Entente at that time, particularly on the seas where the UK held supremacy.