The Opium Wars were a series of conflicts that took place between Britain and China. Option 1, Britain and China, is the correct answer. During the 19th century, Britain wanted to trade with China but faced restrictions from the Chinese government. In order to address this, Britain began smuggling opium into China, leading to widespread addiction and social problems. The Chinese government tried to crack down on the opium trade, leading to conflicts with the British. The First Opium War (1839-1842) ended with the Treaty of Nanking, which forced China to open several ports to trade and cede Hong Kong to Britain. The Second Opium War (1856-1860) resulted in further concessions to Britain, including legalizing the opium trade and granting extraterritorial rights to Western nations in China.