The giganticexplosion that occurred a hundred years ago
A.has remained a puzzle B.lacks sufficient evidence C.is a university professor D.was generated by the explosion E.will kill many animals F.are attacked by aliens正确答案A
The giganticexplosion that occurred a hundred years ago
A.has remained a puzzle B.lacks sufficient evidence C.is a university professor D.was generated by the explosion E.will kill many animals F.are attacked by aliens正确答案A