下列关于科学家与他们的重大发现的说法中正确的是                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           

A．奥斯特

B．欧姆

C．法拉第

D．沈括

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