US-China real exchange rate change at the time of new coronavirus: At the end of April 2020, the consumer price levels in the US and China were virtually the same as they had been at the end of December 2019. During that same period the nominal value of the dollar in terms of Chinese yuan went up by 2.4 percent. This means that between the end of December 2019 and the end of April, the real exchange rate of the dollar against Chinese yuan

a)has remained unchanged.

b)has appreciated by 0.6 percent.

c)has appreciated by 2.4 percent.

d)has depreciated by 2.4 percent.