According to the writer, real opportunities for businesses are those which _____.

A．dependent upon the starting age of candidates
B．worth trying in various social sections
C．of little practical value
D．attractive to every kind of professional

A．the extent of competition
B．people's spending power
C．attitudes to advertising
D．the way people shop

A．is indicative of a pessimism in disguise
B．came into being along with the arrival of computers
C．is deeply rooted in the minds of computered advocates
D．originated from the optimistic attitude of industrialized countries