Last Month,the Exchange Rate Between the U

Last month,the exchange rate between the U.S.dollar and the Japanese yen was 100 yen per dollar.The exchange rate is currently at 110 per dollar.We can say that
a.the dollar appreciated against the yen and the yen depreciated against the dollar
b.the dollar depreciated against the yen and the yen appreciated against the dollar
c.the dollar and the yen both appreciated
d.the dollar and the yen both depreciated