Which of the Following Statements Is True

Which of the following statements is true?

A) Black markets for currency are more likely to exist in countries with overvalued currencies than with undervalued currencies.
B) Black markets for currency are equally likely to exist in countries with undervalued currencies or with overvalued currencies.
C) Black markets for currency are more likely to exist in countries with undervalued currencies than with overvalued currencies.
D) Black markets for currency are more likely to exist in countries with convertible currencies than with non-convertible currencies.