Suppose that yesterday, the U$.$S$.$ dollar was trading on the foreign exchange market at $100$ yen per dollar. Today, the U$.$S$.$ dollar is trading at $105$ yen per dollar.

Which currency appreciated and which depreciated today?

A$.$ The dollar depreciated and the yen appreciated.

B$.$ Both currencies appreciated.

C$.$ Neither currency appreciated nor depreciated.

D$.$ The dollar appreciated and the yen depreciated.

E$.$ Both currencies depreciated.