Creative artists and thinkers achieve communication by ______.

A．Individual contributions combined possess great significance to the public.
B．Good contributors don't neglect the use of internal communication system
C．Everyone except those original people comes under the influence of society.
D．Knowing how to communicate is universal among human beings.

A．discussing the importance of solar energy
B．presenting a history of research on energy sources
C．describing a possible solution to the problem of the cost of photo-voltaic cells
D．advocating increased government funding for research on alternative energy source