请阅读下列短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。

CHRONOLOGICA

——The Unbelievable Years that Defined History

DID YOU KNOW…

  In 105AD paper was invented in China?

  When Columbus discovered the New World?

  The British Museum opened in 1759?

CHRONOLOGICA is a fascinating journey through time,from the foundation of Rome to the creation of the internet. Along the way are tales of kings and queens,hot air balloons…and monkeys in space.

    Travel through 100 of the most unbelievable years in world history and learn why being a Roman Emperor wasn't always as good as it sounds,how the Hundred Years' War didn't actually last for 100 years and why Spencer Perceval holds a rather unfortunate record.

    CHRONOLOGICA is an informative and entertaining tour into history, beautifully illustrated and full of unbelievable facts. While CHRONOLOGICA tells the stories of famous people in history such as Thomas Edison and Alexander the Great, this book also gives an account of the lives of lesser-known individuals including the exploeer Mungo Park and sculptor Gutzon Borglum.

    This complete but brief historical collection is certain to entertain readers young and old,and guaranteed to present even the biggest history lover with somgthing new!

    Peter Thiel,the billionaire co-founder of PayPal,plans to live to be 120.Compared with some other tech billionaires,he doesn't seem particularly ambitious.Dmitry Itskov,the “godfather” of the Russian Internet,says his goal is to live to 10.000;and Sergey Brin,co-founder of Google,hopes to someday "cure death.

    They aren't being ridiculous.Their search is based on real science that could fundamentally change what we know about life and about death.It's hard to believe,though,since the human search for immortality is both ancient and filled with disastrous failures.Around 200 B.C.,the first emperor of China,Qin Shi Huang,accidentally killed himself trying to live forever;he poisoned himself by eating mercury（水银）pills.Centuries later, the search for eternal life wasn't much safer: In J492,Pope Innocent VIII died after blood transfusions from three healthy boys whose youth he believed he could absorb.

    But historical examples haven't discouraged some of the biggest names in Silicon Valley.Thiel,for example,has given $3.5 million to the Methuselah Foundation.Aubrey de Grey,Methuselah's co-founder,says SENS,the nonprofit's main research is devoted to finding drugs that cure several types of age-related damage:"Loss of cells, excessive（过多的）cell division,inadequate cell death,garbage inside the cell,garbage outside the cell,...The idea is that the human body,being a machine,has a structure that determines all aspects of its function,so if we can restore that structure—at the molecular（分子的）and cellular（细胞的）level—then we will restore function too,so we will have comprehensively renewed the body."

    But SENS,which has an annual operating budget of $5 million,is small,compared with the Brin-led Project Calico,Google's attempt to “cure death,”which is planning to pump billions into a partnership with medicine giant AbbVie.Google is secretive,but it's said to be building a drug to copy a gene associated with exceptional life span.

    Then there's the Glenn Foundation for Medical Research,started by Paul F.Glenn in 1965.Since 2007,the foundation has distributed annual "Glenn Awards,"$60,000 to independent researchers doing promising work on aging.The Glenn Foundation also works closely with the Ellison Medical Foundation,a far younger institution (founded in 1997).Ellison's passion project gives out hundreds of thousands of dollars each year to scholars seeking research on aging.Their decision to fund independent research may be paying off.Research projects funded by Ellison and Glenn appear to be developing into a testable means to stave off old age—for lab mice.The question is: Can those lab results be repeated in humans?

    Sweet or salty? What kind of tastes do you like? If like me, you have a sweet tooth and you probably can't resist eating cakes, biscuits or chocolate and will sweeten your tea or coffee with spoonfuls of sugar-delicious! But the taste makes it very easy to ignore the warnings that too much of the white stuff（东西）is bad for our health.

    Consuming sugar is an addiction-the more we eat, the more we want. Today's processed food, like ready meals, is related to the stuff and many fizzy（起泡的）drinks contain seven teaspoons of sugar in just one can. In the UK, statistics show that sugar consumption is at its highest level in history and the government is trying to get the food industry to cut the amount of sugar in popular products like chocolate bars by 20% by 2020.

    Of course, sugary food tastes nice, it can help lift our mood, and a part in it can refresh us. But there are dangers too :a high-sugar diet is linked to putting on weight, and being overweight can increase the risk of getting type 2 diabetes（糖尿病）. With these warning signs, I have considered changing my diet by replacing sugary snacks with fruit and salty biscuits-but that's boring!

I'm not alone. BBC journalist Radhika Shanghani, has gone one step further. Encouraged by some well-knowns and nutritionists promoting a 'zero tolerance' approach to sugar, she gave it up altogether, thinking it would make her healthier. Initially she says, “My first fortnight involves mood swings. I have disturbing headaches and feel permanently hung-over.” These symptoms disappeared but she still found food shopping hard as she was stressing about buying the right things.

    Her experiment wasn't a success. She eventually sought advice from Susan Jebb, professor of diet and population health at Oxford University who said: “Lots of people enjoy sugar and gain pleasure from it, so one has to find a balance between enjoyment and eating the right amount.”

    Are you sick of going to bed late and waking up tired? Then grab your hiking boots and a tent. A new study suggests that camping in the great outdoors for a couple of days can reset your body clock and help you get more sleep.

    The body clock is an internal system that tells our bodies when it's time to go to sleep and when it's time to wake up. Scientists track this clock by measuring the amount of melatonin (褪黑激素) circulating in a person's blood at any given time.

    In a healthy sleeper, melatonin levels rise a few hours before bedtime, stay high through the night, and then settle back down when it's time to wake up.

    In our modern society, however, most of us stay up many hours past sunset and would probably sleep in many hours after sunrise if we could. And the trouble is, your melatonin levels may still be high when your alarm clock goes off in the morning, which leads to fatigue. It may also have other health consequences as well, such as diabetes (糖尿病), overweight and heart disease.

    Professor Kenneth Wright of the University of Colorado in the US wanted to see if our body clocks can be reset by a short stay in nature. His team recruited (招募) fourteen physically active volunteers in their 20s and 30s. Nine went on a weekend camping trip, while the other five stayed home. At the end of the weekend, the researchers reported that in just two days, the campers' body clocks had shifted so that their melatonin levels began to rise more than an hour earlier than they did before they left on the trip. By contrast, the body clocks of the group that stayed home shifted even later over the course of the weekend.

    “This tells us we can reset our clocks fast,” Wright said.

    Therefore, if you want to change your sleep patterns you could try to increase your exposure to natural light during the day and decrease the amount of artificial light you see at night. And if that doesn't work，there's always camping.

    How a few members of the animal kingdom handle the transition to adulthood?

    African elephants

These beautiful beasts come close to imitate teen rebellion. Calves spend a decade with their mothers in female-dominated groups —- and ladies stay there —- but adolescent boys leave mom for noisy crews of bros. In their 20s, they often downsize to smaller male groups.

    Orangutans (猩猩)

Slow metabolism allows these primates to survive food shortages —- times when weather makes ripe fruit scarce. But energy efficiency comes at a cost; growth and maturation take time. Orangutan mamas nurse their young longer than any other wild creature does.

    Orcas(逆戟鲸)

    Killer whales join their mother's familial group for life. This lasting-relationship seems to increase a pup's chance of survival; if mom dies  a young male (under 30) is three times more likely to die than a peer whose mother is alive. Risk of death post-mom-mortem rises as kids get older.

Harp seals

A harp seal's "childhood" lasts just 12 days. A pup's sole purpose during that brief period of coddling(宠爱) is to constantly nurse, gaining a fifth of its birth weight in blubber(鲸脂) every day. Once it's fat —- they become greater from 25 to 80 pounds —- it slides off the ice and takes on the sea.

    Wolf spiders

    Every parent knows that tired toddlers love to hitch a piggyback ride. The wolf spider straps all her babies (40 or 50, on average) onto her back at once, carrying the brood until they are capable of fully functional spider-hood. But luckily she only has to pull them for a few days.