The general public generally believes that early music training can enhance individuals' sound and speech processing capabilities. However, some psychologists have expressed doubts about this. Researchers investigated 1,211 identical twins and 1358 born between 1959 and 1985. For fraternal twins, record their music practice time and evaluate their musical ability. They found that longer practice time does not show better musical ability, for example, a pair of identical identical twins have a music practice time difference of 20228 hours, but their musical abilities are exactly the same. These researchers believe that without the right genes, even 20,000 hours of practice would not make sense, and musical abilities are determined by genes. Which of the following, if true, would best refute the researchers' conclusions? ['Musical ability evaluation uses fingers to simulate fast-paced music, and finger flexibility is genetically affected.', 'Individuals with genetically superior hearing skills may choose to become musicians on their own and practice longer.', 'Identical twins usually have "telepathic" affects the individual\'s performance in the musical ability test.', 'Individuals with poor musical ability will underestimate their practice time in order to maintain psychological balance.']