阅读理解 An argument is appearing in Los Angeles over whether a newspaper should publish teachers' names along with an analysis of how well they do in raising their students' standardized test scores. Some people argue that transparen cy (透明) should exist at all costs, but others hold that it's unfair to label individual teachers using possibly flawed (有瑕疵的) statistics. Some worry that a nger over the forthcoming Los Angeles Times article will make people oppose so-called 'value added' analysis of teacher performance, which is the method the Times uses. 'This incident with the L.A. Times is where the advocates (提倡者) for value-added are getting a bit ahead of themselves,' says Douglas Harris, an education professor. ' Teachers are already feeling under the gun on this kind of thing .' 'Value-added data ' is the latest trend in teacher responsibility: the idea that a student's gain from the previous year's test ? as opposed to his or her overall performance ? can be measured and tied to the latest teacher. 'There are too many variables (变量) in the testing process,' says A.J. Duffy. But he says he opposes using value-added data in evaluations at all, although he acknowledges it could be a useful tool to give teachers feedback. 'I believe in a system that emphasizes the whole student, not just standardized tests,' he says. Proponents (支持者) of value-added say that's a valid criticism, agreeing that no one should expect that student gains on a standardized test could capture the creativity or broader enrichment that goes on in many teachers' classrooms. The District of Columbia which attracted argument for its decision to fire teachers based in part on value-added data, uses that data for 50 percent of the evaluation, relying on other measures such as classroom observation for the rest. 'No one is suggesting using it as a single measure of performance,' says Paige Kowalski. Barnett Berry, a professor, is even more critical of it. Value-added data can be useful, he and others say, but it's important to acknowledge its limitations. It doesn't take into account, for instance, constant student absence and learning gains due to summer school, after-school programs, or supplemental teachers, such as reading specialists. 1. The tone of the underlined sentence is that of _______. A. praise B. warning C. anger D. threat 2. In the opinion of Mr. Duffy, teachers should be judged by _______. A. the value-added data of the times B. students' scores of standardized tests C. the whole development of a student D. the feedback of students and parents 3. The underlined word ' it ' in Para. 6 refers to _______. A. the creativity or broader enrichment B. a standardized test C. classroom observation D. value-added data 4. What's the passage mainly about? A. How well teachers can do in raising students' scores B. Whether teachers should be linked to student's scores C. Who opposes value-added analysis of teacher performance. D. Why the Los Angeles Times plans to publish names of teachers.