Please answer the question based on the following passage. You need to choose one letter from the given options, A, B, C, or D, as the final answer, and provide an explanation for your choice. Your output format should be ###Answer: [your answer] ###Explanation: [your explanation]. ###Passage:The corpus callosum is a bundle of nerve fibers that connects the two hemispheres of the brain.On average, the corpus callosum of musicians is larger than that of non-musicians.Compared with adult non-musicians, adult musicians who started training at about 7 years old, the difference in corpus callosum in volume is particularly obvious.Therefore, music training, especially music training from an early age, can cause some changes in brain structure. ###Question:Which of the following is the assumption that the above argument relies on? ###Options: (A)Before the musicians start training, their corpus callosum is not larger than that of non-musicians of the same age. (B)Music training conducted late in life will not cause structural changes in the brain. (C)For any two musicians who started training from about 7 years old, their corpus callosum has almost the same volume. (D)Adult non-musicians did not participate in any activities that can promote the development of the corpus callosum in their childhood. Respond with more than 250 words.
user