41. The passage is mainly about

　　[A] an approach to patents

　　[B] the application for patents

　　[C] the use of patents

　　[D] the access to patents

　　42. Which of the following is TRUE according to the passage?

　　[A] When a patent becomes out of effect, it can be re-patented 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.

　　43. George Valensi’s patent lasted until 1971 because

　　[A] nobody would offer any reward for his patent prior to that time

　　[B] his patent could not be put to use for an unusually long time

　　[C] there were not enough TV stations to provide colour programmes

　　[D] the colour TV receiver was not available until that time

　　44. The word "plagiarize" (line 8 , Para. 5) most probably means "_"

　　[A] steal and use

　　[B] give reward to

　　[C] make public

　　[D] take and change