Statement I (Assertion A) is considered broadly true. While the exact quote and context are debated, Ernest Rutherford was highly skeptical about the practical possibility of harnessing nuclear energy on a significant scale for power generation based on the knowledge and technology available in the early 20th century. He made statements suggesting it was highly unlikely. Statement II (Reason R) is false. Rutherford's skepticism was not due to doubting Einstein's law E=mc² or the principle of mass-energy conversion. Einstein's formula provided the theoretical basis for the immense energy released in nuclear reactions, which Rutherford's experiments were exploring. Rutherford's doubts were more related to the technical feasibility of creating and controlling a sustained, energy-producing nuclear reaction. Therefore, while Assertion A is true, Reason R is false and does not explain A.