An inventor can generally make a big profit if he ______ his or her invention.

A．all the ideas "new" to us are actually old
B．some "new" ideas can make money without having to be commercialized
C．all "new" ideas first appeared in the form of a patent
D．some "new" ideas may not bring economic reward to their originators

A．some extension of life span
B．some duration of validity
C．some form of reward
D．some kind of monopoly