Difficulty: Easy
Correct Answer: China and Britain
Explanation:
Given data
Concept/Approach
 The First Opium War (1839–1842) was fought primarily between the Qing dynasty of China and Great Britain.
Reasoning
 • Hostilities arose over trade, diplomacy, and opium restrictions. • The Treaty of Nanking (1842) ended the war with concessions to Britain. 
Common pitfalls
 Confusing the First China War with later conflicts involving France or Japan.
Final Answer
 China and Britain
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