涉及机车跨铁路局运行的，提交LKJ基础数据源文件时须明确LKJ（）设置情况。
参考答案：过渡数据径路
Which of the following market structure characterized that a large number of competitors produce (slightly) differentiated products with low barriers to entry（）
A. Perfect competition.
B. Monopolistic competition.
C. Oligopoly.
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