Examination analysis: foreign exchange is the exchange rate between two currencies, foreign exchange rate-foreign currency: RMB. From the table analysis, on April 8th, 100 USD was converted into 626.5 RMB, and on October 2nd, 100 USD was converted into 6 12 RMB. The decline in the exchange rate of the same unit of the US dollar against the RMB shows that the US dollar depreciates, the RMB appreciates and the foreign exchange rate declines. The answer is B.