Being able to multitask--doing several things at the same time--is considered a welcome skill by most people. But if we consider the situation of the young people aged from eight to eighteen, we should think again. What we often see nowadays is that young people juggle an ever larger number of electronic devices as they study. While working, they also surf on the Internet, send out emails, answer the telephone and listen to music on their iPods. In a sense, they are spending a significant amount of time in fruitless efforts as they multitask. Multitasking is even changing the relationship between family members. As young people around them. They can no longer greet family members when they enter the house, nor can they cat at the family table. Multitasking also affects young people's performance at university and in the workplace. When asked about their opinion of the effect of modern gadgets on their performance of tasks, many young people gave a positive response . However, the response from the worlds of education and business was not quite as positive. Educators feel that multitasking by children has a serious effect on later development of study skills. They believe that many college students now need help to improve their study skills. Similarly, employers feel that young people entering the job market need to be taught all over again, as modern gadgets have made it unnecessary for them to learn special skills to do their work. The author develops the passage mainly by  _  .
providing typical examples following the natural time order comparing opinions from different fields presenting a cause and analyzing its effects