Explanation
Correct answer: B.
Choice B is the best answer. Air travel usually requires much more “lead time” than train travel, so short flights end up taking the same amount of time as a train trip to the same destination. But train travel starts to need more “lead time” when the trains approach their capacity limits. This suggests that train companies should add more trains for these routes if they want to encourage travelers to take a train instead of a plane.
Why the other choices are wrong
Choice A
Choice A is incorrect. This inference isn’t supported. The text never discusses “long-haul routes” for either air travel or rail travel, so there is no basis to make this inference.
Choice C
Choice C is incorrect. This inference isn’t supported. The text only mentions these procedures to explain why the “lead time” is so long for air travel. It never suggests that trains need to start implementing these procedures too.
Choice D
Choice D is incorrect. This inference isn’t supported. The goal is to make sure that trains “remain a viable alternative” to short flights, which suggests that anything that makes train travel take longer should be avoided.