The correct answer is B) Britain.
The 1842 Treaty of Nanking ended the war between China and Britain.
The first Opium War started in 1839 and was officially ended with the Treaty of Nanking in 1842. England and China signed the treaty on August 29, 1842. Both, Chinese and British negotiated the treaty on board the HMS Cornwallis ship. One of the results of the treaty was the establishment of the colony of Hong Kong, which remained under the control of the English monarchy until 1997.
