The opening of new railway lines often requires a compromise between the requirement that the road construction cost as little as possible and the requirement that the commercial and trade transportation volume of the new route is as large as possible. This passage supports the idea that the lines of the new railway:. ['Determines the location of emerging trade centers.', 'It depends on whether the distance between the start point and the endpoint is the shortest.', 'It should be the lowest cost line.', 'Will not always build the lowest cost line.']