Which one of the following is the most appropriate statement for the relative purchasing power parity?

A$.$

Relative purchasing power parity does not tell what determines the change in the exchange rate over time.

B$.$

Exchange rate changes due to a relative difference in inflation rates between the two countries.

C$.$

Transaction cost should be zero in order for relative purchasing power parity to hold.

D$.$

Exchange rate adjusts to maintain constant purchasing power.

E$.$

Relative purchasing power parity does show you how the absolute level of the exchange rate is determined.