Questions 11 to 20 are based on the following passage.
【真题来源：2014年6月大学英语四级真题（第二套）Part Ⅲ，Section B，第46-55题】

The Touch-Screen Generation

A) On a chilly day last spring, a few dozen developers of children's apps (应用程序) for phones and tablets (平板电脑) gathered at an old beach resort in Monterey, California, to show off their games. The gathering was organized by Warren Buckleitner, a longtime reviewer of interactive children's media. Buckleitner spent the breaks testing whether his own remote-control helicopter could reach the hall's second story, while various children who had come with their parents looked up in awe (敬畏) and delight. But mostly they looked down, at the iPads and other tablets displayed around the hall like so many open boxes of candy. I walked around and talked with developers, and several quoted a famous saying of Maria Montessori's, "The hands are the instruments of man's intelligence."

B) What, really, would Maria Montessori have made of this scene? The 30 or so children here were not down at the shore poking (戳) their fingers in the sand or running them along stones or picking seashells. Instead they were all inside, alone or in groups of two or three, their faces a few inches from a screen, their hands doing things Montessori surely did not imagine.

C) In 2011, the American Academy of Pediatrics updated its policy on very young children and media. In 1999, the group had discouraged television viewing for children younger than 2, citing research on brain development that showed this age group's critical need for "direct interactions with parents and other significant care givers". The updated report began by acknowledging that things had changed significantly since then. In 2006, 90% of parents said that their children younger than 2 consumed some form of electronic media. Nevertheless, the group took largely the same approach it did in 1999, uniformly discouraging passive media use, on any type of screen, for these kids. (For older children, the academy noted, "high-quality programs" could have "educational benefits".) The 2011 report mentioned "smart cell phone" and "new screen" technologies, but did not address interactive apps. Nor did it bring up the possibility that has likely occurred to those 90% of American parents that some good might come from those little swiping (在电子产品上刷) fingers.

D) I had come to the developers' conference partly because I hoped that this particular set of parents, enthusiastic as they were about interactive media, might help me out of this problem, that they might offer some guiding principle for American parents who are clearly never going to meet the academy's ideals, and at some level do not want to. Perhaps this group would be able to express clearly some benefits of the new technology that the more cautious doctors weren't ready to address.

E) I fell into conversation with a woman who had helped develop Montessori Letter Sounds, an app that teaches preschoolers the Montessori methods of spelling. She was a former Montessori teacher and a mother of four. I myself have three children who are all fans of the touch screen. What games did her kids like to play, I asked, hoping for suggestions I could take home.
"They don't play all that much."
Really? Why not?
"Because I don't allow it. We have a rule of no screen time during the week, unless it's clearly educational."
No screen time? None at all? That seems at the outer edge of restrictive, even by the standards of over-controlling parents.
"On the weekends, they can play. I give them a limit of half an hour and then stop. Enough."

F) Her answer so surprised me that I decided to ask some of the other developers who were also parents what their domestic ground rules for screen time were. One said only on airplanes and long car rides. Another said Wednesdays and weekends, for half an hour. The most permissive said half an hour a day, which was about my rule at home. At one point I sat with one of the biggest developers of e-book apps for kids, and his family. The small kid was starting to fuss in her high chair, so the morn stuck an iPad in front of her and played a short movie so everyone else could enjoy their lunch. When she saw me watching, she gave me the universal tense look of mothers who feel they are being judged. "At home," she assured me, "I only let her watch movies in Spanish."

G) By their reactions, these parents made me understand the problem of our age: as technology becomes almost everywhere in our lives, American parents are becoming more, not less, distrustful of what it might be doing to their children. Technological ability has not, for parents, translated into comfort and ease. On the one hand, parents want their children to swim expertly in the digital stream that they will have to navigate (航行) all their lives; on the other hand, they fear that too much digital media, too early, will sink them. Parents end up treating tablets as precision surgical (外科的) instruments, devices that might perform miracles for their child's IQ and help him win some great robotics competition—but only if they are used just so. Otherwise, their child could end up one of those sad, pale creatures who can't make eye contact and has a girlfriend who lives only in the virtual world.

H) Norman Rockwell, a 20-century artist, never painted Boy Swiping Finger on Screen, and our own vision of a perfect childhood has never been adjusted to accommodate that now-common scene. Add to that our modem fear that every parenting decision may have lasting consequences—that every minute of enrichment lost or mindless entertainment indulged (放纵的) will add up to some permanent handicap (障碍) in the future—and you have deep guilt and confusion. To date, no body of research has proved that the iPad will make your preschooler smarter or teach her to speak Chinese, or alternatively that it will rest her nervous system—the device has been out for only three years, not much more than the time it takes some academics to find funding and gather research subjects. So what is a parent to do?

The author attended the conference, hoping to find some guiding principles for parenting in the electronic age.

American parents are becoming more doubtful about the benefits technology is said to bring to their children.

Some experts believe that human intelligence develops by the use of hands.

The author found a former Montessori teacher exercising strict control over her kids' screen time.

Research shows interaction with people is key to babies' brain development.

So far there has been no scientific proof of the educational benefits of iPads.

American parents worry that overuse of tablets will create problems with their kids' interpersonal relationships.

The author expected developers of children's apps to specify the benefits of the new technology.

The kids at the gathering were more fascinated by the iPads than by the helicopter.

The author permits her children to use the screen for at most half an hour a day.