Final answer:
Without specific details, we cannot definitively identify the individuals being introduced, but the context suggests they could be business people related to international investment.
Step-by-step explanation:
The information provided does not specify the particular individuals being introduced. The categories presented—U.S tourists, U.S investors, foreign tourists, and foreign investors—do not directly align with the options of research scientists, business people, medical doctors, or travel agents. However, if we are to make inferences based on the context provided, two international business people could potentially refer to U.S. investors wanting to make foreign direct investments, or foreign investors looking to invest in the U.S. economy.