16: In recent years, networks of fiber-optic cable have been
replacing electrical wire for transmitting telecommunications
signals. Signals running through fiber-optic cables deteriorate,
and so the signals must be run through a piece of equipment called
a regenerator before being transmitted father. Light-Line is the
leading manufacturer of signal regenerators. Therefore, Light-line
is one of the companies that will most benefit if new long-distance
fiber-optic telecommunications networks are constructed.
Which of the following, if true, casts the most doubt on the
prediction about light-ling’s prospects?
A: Telecommunications signals sent along electrical wires can
travel much farther than signals transmitted through fiber-optic
before needing to be regenerated.
B: Expanding its production of regenerators will require Light-line
to spend proportionately more on labor and materials.
C: The volume of signals that a fiber-optic cable can carry is
several thousand times greater than the volume that can be carried
by an electrical wire of similar size.
D: There are technologies that enable telecommunications signals to
be transmitted without either wire or fiber-optic cable.
E: Several manufacturers are developing regenerator technologies
that will allow signals to be transmitted many times farther than
at present before requiring regeneration.
这道题我选了E，但看到不少选B的答案，不知道哪个对请大家发表一下看法 | 
