Suppose the total market value of all the final goods and services produced in the country of Rushya was $8 billion in 2008 (measured in 2008 prices) and $9 billion in 2009 (measured in 2009 prices). Which of the following statements is definitely correct?

A. Real GDP increased in Rushya between 2008 and 2009.
B. Average price levels increased in Rushya between 2008 and 2009.
C. Production increased in Rushya between 2008 and 2009.
D. Whether real GDP increased cannot be determined with the information given.

Answer: D