According to the passage, where did the first colors for painting come from

A．Human population expands at a straight upward trend.
B．Population growth has shown ups and downs in demographic history.
C．Population growth can not be regarded as a social failure.
D．Increase in population is related to productivity.

A．Xinhua bookstore's reform will be revealed in details.
B．The reforms have been reported to the government.
C．Xinhua bookstore will soon accept foreign investment.
D．The source said we didn't have to remain the majority shareholder.