What did the British use to get a better trade deal with China Patroleum
Opium
Technology

Opium

Explanation:

Opium Wars, two armed conflicts in China in the mid-19th century between the forces of Western countries and of the Qing dynasty, which ruled China from 1644 to 1911/12. The first Opium War (1839–42) was fought between China and Britain, and the second Opium War (1856–60), also known as the Arrow War or the Anglo-French War in China, was fought by Britain and France against China.

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ok sorry the answer is a. by their religion