[单项选择]In the thirteenth century, in order to discover what language a child would speak if he heard no mother tongue, Frederic Ⅱ told the nurses to keep silent, and all the infants died before the first year. But dearly there was more than language deprivation here. What was missing was good mothering. Without good mothering, in the first year of life especially, the capacity to survive is serious affected.
Today no such ruthless deprivation exists as that ordered by Frederick. Nevertheless, some children are still backward in speaking. Most often the reason for this is that the mother is insensitive to the cues and signals of the infant, whose brain is programmed to mop up language rapidly. There are critical times, it seems, when children learn more readily. If these sensitive periods are neglected, the ideal time for acquiring skills passes and they might never be learned so easily again. A bird learns to sing and to fly rapidly at the right time, but the process is slow and hard
A. The child’s brain is highly selective.
B. The faculty of speech is inborn in man.
C. Children do not need to be encouraged to speak.
D. Most children learn their language in definite states.