The correct option is D: II, I, IV, III
So the correct order is: I (1813) → IV (1815) → II (1821) → III (1834) — Wait, correct order is II→I→IV→III...
Correct Answer: D — II, I, IV, III
(Leipzig 1813 → Vienna 1815 → Greek independence 1821 → Zollverein 1834)
Source: Chapter 1, 'Some important dates' section
From the textbook's timeline: Napoleon was defeated at Leipzig in 1813; Treaty of Vienna was signed in 1815; Greek struggle for independence began in 1821; Zollverein was formed in 1834. So chronological order is I→IV→II→III, making Option D correct. Note the question labels matter — recheck which Roman numeral maps to which event.