The discovery of mitochondrial DNA (mtDNA) significantly impacts many areas of science, such as evolutionary biology, inheritance research, and forensic science, but does not affect the study of cork bark. Therefore, the correct answer to the question is option D, the study of cork bark, as it is unrelated to mtDNA. Cork bark focuses on practical applications and properties, rather than genetic analysis.
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Mitochondrial DNA (mtDNA) significantly impacts areas like evolutionary biology, inheritance research, and forensic science. However, it does not affect the study of cork bark, which is unrelated to genetic analysis. Thus, mtDNA's discovery had no impact on the study of cork bark. ;