题目内容：

    Dolphins are universally regarded as some of the cleverest creatures in the world. In captivity ( 圈养), they can be trained to complete complex tasks such as jumping through hoops and somersaulting through the air.

But their intelligence doesn’t stop there. In a recent study of cetaceans (鲸目动物)--a group of animals that includes dolphins and whales--researchers created a list of intelligent behaviors observed in 90 different cetacean species, reported the Guardian. For example, the smartest cetaceans hunt in groups, share knowledge through mimicry (模仿) and even care for each other's children. Some even consider their behavior to be human-like.

“There is the saying that ‘it takes a village to raise a child’ seems to be true for both whales and humans,”

Michael Muthukrishna of the London School of Economics, co-author of the study, told the Guardian.

However, cetaceans don’t just use their brain power for survival. The study suggests that dolphins might even gossip. That's because some species greet each other with specific whistles, just as humans greet each other by name, the Guardian reported. Sometimes, a group of dolphins whistles the “name” of a dolphin that isn't there. Could they be speaking about their “friend” behind its back?

For the researchers, dolphin small talk is a big deal. As they found that the most social cetaceans also have the largest brains, they argue that cetacean intelligence developed to meet the demands of complex social groups.

Known as the “cultural brain hypothesis (假设),” it had only been used to explain the intelligence of humans and other primates (灵长目动物). The new study aimed to find a common pathway for the evolution of intelligence among biologically different species.

“It is interesting to think that whale and human brains are different in their structure but have brought us to the same patterns in behavior, ” Luke Rendell, a biologist at the University of St Andrews, told the Guardian.

Indeed, we still have a lot to learn about our intelligent ocean-dwelling neighbors. “We don’ t have to look at other planets to look for aliens,” Muthukrishna told the Guardian, “because we know that underwater there are these amazing species with so many parallels to us in their complex behaviors.”

1.The recent study was intended to ______.

A.learn more about intelligent creatures of the sea

B.explain the intelligence of humans and cetaceans

C.create a list of intelligent behaviors of different cetacean species

D.see whether the intelligence of different species evolved in the same way

2.The implied  meaning of the underlined part in Paragraph 3 is that ______.

A.villagers have the responsibility  to raise any child in the village

B.like human beings, whales even help raise each other’s babies

C.cetaceans have social behaviors very similar to human beings

D.it is not easy for one villager to take care of his or her own child

3.It can be inferred from the passage that ______.

A.it is unnecessary to look for aliens and do research into them

B.some cetaceans have the same intelligence as human beings

C.both dolphins and whales greet each other with specific whistles

D.both dolphins and whales have a lot in common with humans in behaviors

4.What is the best title for this passage?

A.Aliens living underwater B.A study of intelligent dolphins

C.Intelligent creatures of the sea D.Reasons for the intelligence of sea creatures