Which of the following statements is true? O a. The conversion of domestically calculated GDP per capita values using a purchasing power parity (PPP) exchange rate will make economies with relatively high price levels appear larger than those with relatively low price levels. O b. The purchasing power parity (PPP) exchange rate is calculated by comparing the cost of a commonly consumed non-tradeable good, such as a Big Mac, in all countries. O c. The purchasing power parity (PPP) exchange rate can only be calculated if the economy produces tradeable goods. O d. The purchasing power parity (PPP) exchange rate is calculated by comparing the price of a common tradeable good produced in all countries. O e. The conversion of domestically calculated GDP per capita values using the market exchange rate will yield GDP per capita values that reflect international differences in both the quantity of output produced and the relative price level in the country