如果用一组词来概括1368—1840年的明清(鸦片战争前)时期总的历史特点，下列概括最准确的一项是（     ）

    Zhang Ming, a college student from Shandong, created a 9-page “WeChat guide”. With drawings and simple words, the step-by-step guide explains how to send messages, take pictures and make video calls. Zhang made the guide for his parents. “My parents are getting old. They need an easy way to learn how to use new technology.” He said.

    Zhang's experience is common nowadays. Worldwide, 40 percent of parents learn about new technologies, including computers, mobile Internet and social media, from their children, according to a study from the International Communication Association in 2014.

    Parents used to teach their kids about almost everything. Now for the first time, the teachers become the students, and the students turn into the teachers.

    The change of roles comes from the rapid development of society and technology, says Zhou Xiaohong, a sociology professor from Nanjing University. Zhou said the Internet and other forms of media give children ways to get information besides from asking older generations(长辈). Therefore, in the age of information, it's possible that children know more than their parents do.

    According to the China Internet Network Information Center(CINIC), 56.7 percent of Internet users and 67.2 percent of social media users in China are under the age of 30. The younger generation usually acts as a link between their family and the new environment. But when they teach their parents new technologies, parents can connect to the new world by themselves, noted Zhou.

    In Zhang Ming's eyes, teaching his parents about WeChat brings him closer to his parents. “People can communicate more by using new technology. Why should we keep our parents out?” said Zhang.

    It's comforting to think if you were somehow swallowed by a whale, you'd simply hang out in his stomach until he eventually spat you out, unharmed and whole. Unfortunately, your chance of ending up in this type of situation is pretty low.

    In 2012 reporter Ben Shattuck read the records at the New Bedford Whaling Museum Research Library. Despite his extensive research at one of the most comprehensive whaling archives(档案), he failed to find a single report of anyone ever being swallowed alive by a whale. He found plenty of reports of whalers who were bitten or injured by the creatures, and several who died after fighting with a whale, but none related to swallowing.

    With whales' large mouths, it certainly seems possible that a whale could swallow someone whole, so why is it so unlikely? Baleen whales, or whales without teeth, are some of the largest creatures on the planet. Despite their massive size, baleen whales could never get you into their bellies thanks to their relatively small esophagus(食道). These whales are designed to eat small sea creatures, and the opening in their throat is only about as large as a basketball, so you'd never make it that far.

    But what about toothed whales? Sperm whales eat whole seals, so you could easily fit down their throats and into their stomachs. However, once you reached the first of the sperm whale's four stomachs, your journey would probably end quickly. Not only would the whale's stomach acid make quick work of you, but you'd experience a distinct lack of air on the inside. Actually, you're more likely to get eaten or injured as you try to make it past the sperm whale's sharp teeth. Plenty of whalers, have fought with sperm whales and lost their hands or lives due to these mean teeth.

爱迪生一生经历了无数次失败,但每次失败后他都能不断寻求和发明更多的东西。这位伟大的科学家从自己“屡战屡败”的经历中总结出一条宝贵的经验。他说:“失败也是我需要的,和成功一样对我有价值。只有在我知道一切做不好的方法以后,我才知道做好一件工作的方法是什么。”

结合上述事例说明自信者的哪些心理品质有助于成功。