Final answer:
A high interest rate is most likely to attract foreign investors and increase the value of a country's currency.
Step-by-step explanation:
The most likely factor to attract foreign investors and increase the value of a country's currency is a high interest rate. When a country offers a higher interest rate, it makes its financial markets more attractive to foreign investors seeking higher returns on their investments. These investors will then need to convert their currency into the country's currency to invest, which increases the demand and value of the country's currency.
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