题目内容：

Like toolmaking,teaching was once thought to be an exclusive（独有的）capacity of the human mind.It is not actually.

“Teaching”requires this:one individual must take time from their own task to demonstrate and instruct with effort and the student must learn a new  skill.That’s a tall order.

When a young chimpanzee watches a skilled adult and then imitates（模仿）,that’s learning.But the adult has not taken time specifically to instruct,so it is not teaching.In the honeybees’ amazing dance,the dancer takes time to indicate information about a source of food,but observers learn no new skill.They do take time to show,but they do not pass on new skills to learners.

Dolphins teach.Atlantic spotted dolphin mothers sometimes free a caught fish in the presence of their youngsters and let their youngsters chase it,catching it again if it’s getting away.Dolphin youngsters also position themselves alongside mothers who are scanning sandy bottoms for hidden fish,and the mother spends extra time demonstrating.

Other teachers include:housecats who bring back live prey and let their young learn to catch it,and meerkats（猫鼬）who first bring to their growing young dead scorpions（蝎子）,then disabled ones,to demonstrate how to remove the poisonous part on their tails.

Like toolmaking and teaching,imitation is also considered to reflect high intelligence.In South Africa lived a baby dolphin named Dolly.One day while she was just six months old,Dolly was watching a trainer standing at the window smoking a cigarette,blowing puffs of smoke.Dolly swam to her mother,got a mouthful of milk,then returned to the window and released a cloud of milk that surrounded her head.The trainer was“absolutely astonished”.Somehow Dolly came up with the idea of using milk to represent smoke.Using one thing to represent something else isn’t just imitation.It is art.

1.What does the underlined phrase“a tall order”probably mean in paragraph 2?

A. A clear instruction.    B. A high risk.

C. A difficult requirement.    D. A useful purpose.

2.What do we know about honeybees’ dance?

A. Presenting.    B. Learning.

C. Imitating.    D. Teaching.

3.What can we infer about animals that can teach?

A. Bees show their dance to younger generations.

B. Housecats teach in a way similar to dolphins.

C. Young dolphins must learn how to free a fish.

D. Meerkats have poisonous parts on the tails.

4.Why does the author use Dolly’s example?

A. To prove smoking can affect other animals.

B. To explain dolphins are capable of making art.

C. To show animals can be surprisingly intelligent.

D. To stress milk is to dolphins what smoking is to men.