单项选择题

下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文，并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。
第一篇
Thinking from a teacher
As the fall semester ended, my students had a chance to turn to tables on their teacher. They got to grade me anonymously, assessing the clarity of my thinking, my organizational skills and the depth of my knowledge. At their best, such evaluations keep me alert to what works and what does not. Students reflect my performance back to me, and I am glad to learn what they think of my teaching, so that I might try to improve.
I am also aware that the students’ comments become the primary evidence of my abilities, a paper trail following me throughout my career. When I come up for review, the promotion committee will examine my evaluations to determine just what kind of teacher I am.
There is, of course, nothing wrong with accountability. But this system assumes that what students need is the same as what they want. Reading my evaluations every semester has taught me otherwise. Many students’ expectations for their courses have changed, reflecting, in part, the business model more universities are following. Classes are considered services, and parents are eager to get their money’s worth from their children’s education. Students feel pressure from their parents to derive practical use from their courses.
This could make sense for an engineering course, but in my field, creative writing, which rarely churns out polished 21-year-old writers, it is trickier to provide the results that the career-minded student craves. Then I stumbled upon some dubious teaching techniques, reversed the criticisms of these chronically unhappy students and improved my student evaluations for the semester. My record would reflect a smart, attentive, encouraging teacher. But I would argue that I taught these students little. They loved me because I agreed that writing should be easy.
I know other teachers who have done the same thing: teach your heart out to the teachable but be sure to please the unteachable, to keep your ratings high like a politician trying to improve his poll results.
I believe in the struggle, and most students I have met do too. But I still can’t help wincing when I read, "The instructor is mean." "Marcus is not committed to my work." "This class sucks." The business model has taught me that the customer is always right. But maybe a few more dissatisfied customer would mean a better learning experience.
Why does the author say "classes are considered service"