The second argument would be most convincing to the person because they believe in the importance of advancing science and benefiting millions of people. If it is shown that testing on animals does not reliably predict results in human beings, then it brings into question the effectiveness and validity of using animals for testing. This could make them reconsider their beliefs and potentially look for alternative methods of testing.

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If it is demonstrated that testing on animals does not consistently produce accurate results in human subjects, it could challenge their stance on the efficacy of animal testing and prompt them to explore alternative testing methods. This new perspective may lead them to reassess the value of advancing science and benefiting society through animal testing.