单项选择题

Passage One
Questions 57 to 61 are based on the following passage.
Recently, a student used his Personal Digital Assistant (PDA) to film a female teacher berating (训斥) and tearing the work of a classmate. The public discussion that the incident caused was confined initially to the virtual community in which the video clip was posted. However, when it came to the media’s attention, it quickly became a major topic in the education circles. The reactions so far suggest that the focus of the debate has been on one question: Whom to blame
Teachers who are anxious to defend their professional integrity have tried to put the blame on the students. They cited intrusion of privacy as the reason for their request to the Ministry of Education (MOE) to ban PDAs in schools. On the other hand, some parents and students have taken a different position. They feel that the teacher is also at fault, Caught up in the war of words between both sides, people are no longer interested in the "truth" of the matter which seems now unimportant. It was left to newspaper commentaries to identify the central issue of the controversy, by highlighting the deep underlying problems in our educational system.
For those responsible for educating the young, this PDA episode conveys the message that "Times have changed", a reality that must have been felt even more acutely by the female teacher when reflecting on this unpleasant experience. Different times call for different professional approaches in education. The ability to understand the students they are teaching has always been the hallmark of successful teachers. Despite some factors, the outburst by the teacher shows a lack of professionalism on her part. Besides, there are rules under current system to deal with recalcitrant students. Also, it illustrates an issue we are familiar: What to do with new technology With PDA, the new technology, the interaction between the teacher and students in classroom has been changed. The author’s purpose in writing this passage is to ______.