Economic trends in China's Gross Domestic Product over a 50-year period can best be described as

A. a gradual but steady decline in economic activity
B. relatively stable with low levels of economic activity from the 1950s to the late 1990
C. a gradual but steady increase in economic activity
D. initially stable with a drastic increase in economic activity starting in the late 1980s

D. initially stable with a drastic increase in economic activity starting in the late 1980s