Upon arrival at the international airport in the country of Canteberry, Charles Alt exchanged $200 of U.S. currency into 1,000 florins, the local currency unit. Upon departure from Canteberrys international airport on completion of his business, he exchanged his remaining 100 florins into $15 of U.S. currency. How much gain or loss did Charles experience when he converted the 100 florins to U.S. dollars upon returning to the U.S.?

A. Loss of $5

B. Gain of $5

C. Loss of $10

D. No gain or loss