By saying "the growth of the proportion...to younger generations." (Line2, Para. 5), Anthea Tinker really means that ________.
A. currently wealth flows from old generation to younger generation
B. traditionally wealth flows from younger generation to old generation
C. with the increasingly big population of over 50, the trend arises that wealth flows from younger generation to old generation
D. with more and more people of over 50, traditions have been reversed
