The correct response is: These Western imperialist powers saw that Great Britain had gained money and power through the Treaty of Nanking and they wanted the same for themselves.
After the Treaty of Nanking, which marked the end of the First Opium War and imposed unequal terms on China, other Western powers recognized the financial and territorial opportunities that such treaties provided. They sought to establish their own concessions and spheres of influence in China, leading to similar unequal treaties being signed with the U.S., France, Russia, and other nations.