听下面5段对话或独白。每段对话或独白后有几个小题，从题中所给的[A]、 [B]、[C]三个选项中选出最佳选项，并标在试卷的相应位置。听每段对话或独白的，你将有5秒钟的时间阅读各个小题；听完后，各小题将给出5秒钟的作答时间。每段对话或独白读两遍。 Why does the woman work so hard

[A] They have been replaced by electric trains.
B. They have been used for special railway service.
C. They have become more comfortable.

A． A musician.
B． A traveler.
C． A school teacher.