In general, as soon as the newborn child’s muscles, sense organs, and nerves are fully formed, the child begins to use them. But

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问题     In general, as soon as the newborn child’s muscles, sense organs, and nerves are fully formed, the child begins to use them. But much of the human nervous system is not fully developed until the child is a year or two old, and some parts, such as the corpus callosum, continue to mature for at least the next 20 years.
    The general pattern of bodily development is from head to foot. Simple skills, such as head movements, appear first because the structures that control these skills are among the first to mature. More complex behavior patterns, such as crawling, standing, and walking, come much later in the developmental sequence than head movements do.
    The motor centers in the brain are connected by long nerve fibers(usually through one or more synapses) to the muscles in various parts of the body. Since the head muscles are closer to the brain than the foot muscles, according to one theory, the head comes under the control of the motor centers long before the feet do. The appearance of a new motor skills(such as crawling and grasping)always suggests that a new part of the child’s body has just matured-that is, that the brain centers have just begun to control the muscles involved in the new motor skill.
Why do the head muscles come under control of the motor centers long before the foot ones do? (  )

选项 A、Because the head has a shorter distance to the brain than the feet do.
B、Because the head muscles have a longer distance to the brain than the foot ones do.
C、The head muscles are more important than the foot muscles.
D、All of the above are not true.

答案A

解析 细节题。“为什么头部肌肉要比脚部肌肉更先受到中枢神经的控制?”文章第三段第二句话Since the head muscles…long before the feet do便是本题答案。
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