单选题

　　[完成句子]Sagan was noted for the vigour of his logic style， especially when criticizing some piece of pseudoscience（伪科学）。 I remembered a 1973 AAAS meeting at which he destroyed the theories of Immanuel Velikovsky， who was maintaining that only a few thousands of years ago， Venus had repeatedly collided with Earth and Mars； events well noted. Velikovsky said， in the bible.

　　In Sagan‘s opinion， Velikovsky might be__________.

　　A、a member of the National Academy of Science

　　B、a pseudo-scientist

　　C、a science populariser

　　D、a reporter