单选题
Visual impairment carries with【C1】______ ability to travel through one's physical and social until adequate orientation and mobility skills have been established. Because observational skills are more limited, self-control within the immediate surroundings is limited. The visually impaired person is less able to anticipate【C2】______ situations or obstacles to avoid. Orientation refers to the【C3】______ map one has of one's surroundings and to the relationship between self and that environment. It is best generated by moving through the environment and【C4】______ together relationships, object by object, in an organized approach. With【C5】______ visual feedback to reinforce this map, a visually impaired person must rely on memory for key landmarks and other clues, which enable visually impaired persons to【C6】______ their position in space. Mobility is the ability to travel safely and efficiently from one point to another within one's physical and social environment. Good orientation skills are necessary to good mobility skills. Once visually impaired students learn to travel safely as pedestrians (行人), they also need to learn to use public transportation to become as【C7】______ as possible. To meet the【C8】______ demands of the visually impaired person, there is a sequence instruction that begins during the preschool years and may continue after high schools. Many visually impaired children lack adequate concepts regarding time and space or objects and events in their environment. During the early years much attention is focused on the development of some fundamental【C9】______ , such as inside or outside, in front of or behind, fast or slow, which are essential to safe,【C10】______ travel through familiar and unfamiliar settings.