The demonstrators threatening to disrupt the meeting are from______. groups.

A．There was a new dependence on communication with people far away and the use of money.
B．The alphabet and numerical system was introduced.
C．The old methods of farming now required the use of complex machines.
D．The global economy made mass electronic communication very common.

A．The teachers came to the children' s homes.
B．The children acquired the information they needed by direct experience.
C．Children were taught in small, personalized groups at home.
D．Parents would teach children the three R' s themselves.