如图所示，用“•”表示方向垂直纸面向外的磁场，与磁场方向垂直的三条导线甲、乙、丙中都通有电流，下列说法中错误的是（　　）

阅读下文，完成下列各题。

玉瑛子

       ①不曾可以寻觅，也不曾有任何准备。似乎是猝不及防，它撞进了我的视线。

       ②在那方柜台的一隅，它静静地、安详地、自然地停留着，姿势优美。四周的喧闹，仿佛和它没有任何关系。那些来来去去的目光，被形形色色的宝石的光华吸引着，而忽略了它的存在。它于自己的世界孤独地美丽着，有些傲气，有些不屑，有些与世无争。那一块冰凝的翠色，那一缕剔透的晶莹，那一掬澄澈的水灵，那一抹温馨的柔润，于繁华之中，于喧嚣之中，碰疼了我的心。

       ③哦，那一块天然的翡翠，一块美玉。

       ④那一天滂沱大雨。我为避雨无意中躲进那间小店，无意回眸之间，就那样与它相遇。

       ⑤尽管小心翼翼、呵护有加，意外还是发生了。

       ⑥或许因为之前没有佩玉的经验，而致使佩戴方法有失正确；或许因为过度喜爱，从而太过频繁地摆弄……正如它猝不及防地闯入我的生活，意外在那一日猝不及防地降临。

       ⑦那美丽、珍稀的翠色之间，出现一道小小的裂隙。很小，但很清晰。发现它受伤的那一刻，我的心脏仿佛和它一同开裂。我感受到它的疼痛。它受伤的样子，令我的心血流不止、肝肠寸断。尽管裂隙很小，可它毕竟存在着。它妨碍了它的美丽，影响了我观赏它的心情。可摆在眼前的它，已然不再是那个完美无暇的玉，它无法回到从前。

       ⑧只好把它从胸前摘下。

       ⑨扔掉吗？实在是舍不得；退还给卖玉的人吗？那几乎没有可能。留着它，触景生情。我只好选择了逃避。把它封存起来，紧锁于抽屉，长时间不打开，避免碰触，任凭岁月将它埋葬。

       ⑩又一个阴雨天，雷同的天色让我情不自禁想起它的到来。想起初拥它的激动和欣喜。怀念它在我怀抱的那美丽时光。

       ⑪我重新走进那间玉店。我问卖玉的人：有没有什么办法能够使玉的伤口复原？卖玉的人拿出一块又一块的玉给我看。它们每一块都身价高昂。但几乎每一块，放在聚光灯和放大镜下仔细琢磨，都能发现它的明显缺陷。你看，这一块晶莹剔透，它的水很好，水好自润，不易出裂，但易有杂质，看见这个小黑点了吗？就像美人的身体上长了颗痦子，你能因为她长了一痦子就不是美人了吗？再看这一块，这片绿色娇艳欲滴，它的翠真是太喜人了，可惜水不足，缺水就干燥，干燥就多絮，这是天然石头自身携带的绵絮，你能因为几团绵絮的存在就贬降它的价值吗？

       ⑫我无言以对。

       ⑬卖玉的人告诉我：天然的石头，十石九裂。正如同人，世间没有完美无缺的人，这世上，完美无瑕的翡翠，也是少之又少，如果有，那一定是稀世罕见、无价之宝了。翡翠虽然质地坚硬，但它也是有生命的活物。既有生命，就需要拥有者用情感、用爱心去浇灌它，去呵护它，去滋养它。

       ⑭我问：这世上就没有不怕磕碰、不怕摔打的翡翠？卖玉的人笑了笑：如果有，一定是人造的，是假的。

       ⑮我问：受了伤的玉，还有收藏价值和增值功能吗？

       ⑯卖玉的人回答我：当然有。那要取决于什么样的伤，伤的程度。你的这块，只是一个浅表性的小小的纹隙，不是根本性的致命伤，你要经常佩戴，不过要吸取上次的教训，一定使用正确的佩戴方式……你把它当成身体的一部分，好好地养它，好好地珍爱，但不能因为珍爱就无时无刻过分地关注它……相信只要经过一定时间，就像人的皮肤受了点小伤，伤口自然会愈合。

       ⑰哦，能养好它？

       ⑱我顿觉惊喜：那需要多长时间？一月？一年？

       ⑲卖玉的人又笑了：玉毕竟是石头。养玉，需要几十年，或者一辈子。如果用一辈子的时间把它养好了，也不失为一块传家宝。就像人的情感，那历经无数坎坷挫折、经过了漫长岁月水与火的淬炼，那最终留下来的，才是真正的无价之宝……

                                                                                                                                                                                                               （有改动）

阅读下列短文, 从每小题所给的A、B、C、D四个选项中, 选出最佳选项.

    For too many, the damage begins early in life. Four out of 10 babies born in the United States do not form a strong relationship with either parent, and they will pay for that the rest of their lives.

    New research from Princeton University confirms what other researchers have already found: The number of babies born into families that are too poorly equipped(装备、配备) to give them a fair chance of having a successful life is very big.

    That finding is supported by many other research Projects, including a study from the University of Rochester showing that nearly one-third of U.S. parents don't know what to expect from their new horns, or how to help them grow and learn and get along with others. Babies, as others have pointed out, don't come with an owner's manual.

    The basic problem, according to the Princeton study, is 40 percent of infants in the U.S. live in fear or distrust of their parents, and that will turn into aggressiveness（侵犯）, defiance（挑衅） and hyperactivity（多动） as they grow into adults.

    Of that number, 25 percent don't have a close relationship with their parents because the parents don't satisfy their needs. And 15 percent find their parents so troubling that they will avoid them whenever possible.

    That will not necessarily result in a lifetime of violence(暴力), but it will make living a successful life much more difficult.

"They can overcome(克服) it," sociologist (社会科学家) Sophie Moullin of Princeton, lead author(作者) of that study, said in a telephone interview. "It's not a make or break situation, but they might find it harder to control their behavior."

    Moullin, along with coauthors from Columbia University and the University of Bristol in England, analyzed(分析) more than 100 research projects, to reach their conclusions.

    There are many factors, including poverty(贫穷), ignorance（无知）, and stress among parents who are so busy with their own problems that a new child is sometimes more than they can deal with.

    Yet strong relationships, the researchers say, are amazingly simple to achieve.