A logical reasoning problem, In the past five years, five w-160 passenger planes have been crashed. In the face of the accusation that the w-160 design was wrong, the w-160's life is not good The manufacturer explicitly denied it on the ground that every investigation into the w-160 air crash showed that the cause of the crash was flying The operator made a mistake Which of the following must be assumed in order to make the above refutation of the manufacturer Tenable? A if the pilot doesn't make mistakes, the w-160 won't crash B the pilot's misoperation has nothing to do with the design of any part of the w-160 C the conclusion of every investigation on w-160 air crash is credible The answer is to choose B and C. why not choose a? Please analyze in detail,

A logical reasoning problem, In the past five years, five w-160 passenger planes have been crashed. In the face of the accusation that the w-160 design was wrong, the w-160's life is not good The manufacturer explicitly denied it on the ground that every investigation into the w-160 air crash showed that the cause of the crash was flying The operator made a mistake Which of the following must be assumed in order to make the above refutation of the manufacturer Tenable? A if the pilot doesn't make mistakes, the w-160 won't crash B the pilot's misoperation has nothing to do with the design of any part of the w-160 C the conclusion of every investigation on w-160 air crash is credible The answer is to choose B and C. why not choose a? Please analyze in detail,

First, the main premise: every investigation conclusion is credible. Second, the pilot's operation error has nothing to do with the design of any part of the w-160