Of all the animals in the animal kingdom, which one (aside from man) is the cleverest?
There are several ways of measuring the intelligence of animals. In one test a scientist sets three same cans on a table. While the animal watches, he puts food under one of the cans. Then he leads the animal away. Some time later, he brings it back to see if it remembers which can has the food. No smelling is allowed; the animal must go directly to the correct can or it fails.
This is called a delayed-response test. The idea is to find out how long an animal’s memory can keep information. The scientists would try showing the cans to the animal one hour later, or two hours later, or even a full day later. They discovered that chimpanzees and elephants have the best memory, and were able to remember the correct can for at least twenty hours. No other animal is close. Dogs came next, but they only remember for nine hours.
To settle the matter, the scientists designed a huge maze (迷宫) and ran the chimps and elephants through it. The maze was very difficult, with many blind paths and dead ends. It took the chimps ten minutes to find their way out. The elephants needed half an hour. Even allowing for the elephants’ slower rate of speed, the test shows that chimpanzees are the cleverest animals.
From this and other tests, the scientists drew the following conclusion: an animal’s intelligence depends on the size of its brain in proportion (比例) to the size of its body. The elephant’s brain weighs ten pounds. But this is only 1/600th of its 6,000 pounds body. A chimp’s brain weighs about one pound, or 1/120th of its total body weight. So in proportion to its body size, the chimp has four times as much brain as the elephant----more brain for less body. The chimp is the champ!
Which is the best title?

A．The Elephant’s Memory	B．The Cleverest Animal
C．Judging Intelligence	D．The Chimp’s Brain

The main idea of this passage is that _____.

A．there are several ways of measuring the intelligence of animals

B．chimps and elephants have the best memory

C．intelligence tests show that the chimp is the cleverest animal

D．the scientists designed a huge maze and ran the chimps and elephants through it

The delayed-response test is designed to test an animal’s _____.

A．eyesight

B．intelligence

C．learning ability

D．memory

The passage tells that elephants _____.

A．never forget things	B．are more clever than chimps
C．are slower-moving than chimps	D．have better memories than chimps

According to the passage, a rhinoceros (犀牛) that weighs 2100 pounds, and has a 3-pound brain is _____.

A．as clever as a chimp	B．more clever than an elephant
C．less clever than an elephant	D．as clever as an elephant