Final answer:
The most appropriate method of international business for Boca Co. to have complete control over its operations in Japan is the establishment of a Japanese subsidiary.
Step-by-step explanation:
If Boca Co. wants complete control over its operations in Japan, the most appropriate method of international business for them would be the establishment of a Japanese subsidiary. By establishing a subsidiary, Boca Co. can have complete ownership and control over its operations in Japan. This allows them to tailor the operations to their specific requirements and strategies.
In contrast, a joint venture involves partnering with another company, which means Boca Co. would not have complete control over the operations. Licensing involves granting another company the right to use Boca Co.'s intellectual property, but it does not provide complete control over operations. Lastly, partial acquisition of an existing Japanese firm would also not provide full control since Boca Co. would only have a partial ownership stake.