Answer:
C. Opium Wars
Step-by-step explanation:
There were two opium wars that mainly had Chinese forces against British forces. China had lost both times and would gradually lose economic hubs (coastal cities) to Britain and other European Powers. The reason for these wars was the restrictions on opium, China had placed in. The British had made a lot of money off of the opium trade, they were not keen on losing such a trade so they went to war.