Conclusion I: Natural gifts need nurturing and care. This conclusion is correct because the statement suggests that while a good voice is a natural gift, one still has to practice to improve. This implies that even natural gifts need nurturing and care to excel in a field, like music.

Conclusion II: Even though one’s voice is not good, one can keep practising. This conclusion is incorrect because the statement does not mention that a bad voice can be improved through practice. It only emphasizes that even with a natural gift (good voice), practice is needed to excel. It does not imply that practice alone can overcome a bad voice.

Therefore, only conclusion I follows from the given statement.