Which of the following is TRUE according to the passage?A.When a patent becomes out of eff
Which of the following is TRUE according to the passage?
A.When a patent becomes out of effect, it can be repatented or extended if necessary.
B.It is necessary for an inventor to apply for a patent before he makes his invention public.
C.A patent holder must publicize the details of his invention when its legal period is over.
D.One can get all the details of a patented invention from a library attached to the patent office.