Final answer:
The strategy being used by the financial officer who is managing foreign currency for an international firm, by holding a larger supply of yen in anticipation of its rise, is known as speculation.
Step-by-step explanation:
As the financial officer for an international firm, the strategy you are using by keeping a larger supply of yen on hand in anticipation of its rise due to increased production is known as speculation. This approach involves anticipating future movements in exchange rates and holding a currency with the expectation that it will increase in value. Unlike hedging, which is focused on protecting against risks associated with currency fluctuations, speculation is more about taking on risk with the potential for financial gain.