题目内容：

It has long been thought that elephants rely on their large ears and bathing in rivers to stay cool in hot climates. New research，however，has showed that the world's largest land animals have a secret trick of controlling their body temperatures.

Scientists have long been puzzled by temperature regulation(调节)in elephants. Generally，animals with large bodies tend to hold more heat because，compared to their size，they have a small surface area for heat to escape from. Elephants，with their heavy­weight frames，would appear to be at a disadvantage in the heat of their African and Asian habitats，especially because they have thick fur to protect them from bushes and trees.

Scientists thought that these creatures，which weigh up to 13 tons when fully­grown，grow large ears to help them stay cool. The skin on the ears is thinner，so blood which flows into them cools down more easily. But findings by researchers at two universities in Vienna have showed that elephants are also able to cool down by increasing the blood flow to skin patches(斑) in other parts of their bodies.

The researchers studied six African elephants at Vienna Zoo as they moved between outdoor and indoor environments to see how the temperature on their skin surface would change. They found up to 15 “hot spots” all over an elephant's body surface，in addition to large patches on the ears. The study shows how these patches expand as the air temperature increases and more blood flows nearer to the skin surface. Other experiments show that elephants in the wild use the same “windows” to control their body temperature.

Elephants have two additional ways to stay cool: flapping(拍打)the ears and bathing. Together with these tricks，the skin hot spots allow the animals to keep their body temperature always at about 36 degrees—one degree less than humans'.

1.What can we know about the elephants?

A. They have thick fur to protect them.

B. They live in cool areas in Africa and Asia.

C. They can weigh up to 3 tons when fully­grown.

D. They are afraid of water and rivers.

2.The function of the thinner skin on elephants' ears is to________.

A. control their body temperature    B. help hold more heat

C. drive away insects    D. keep sensitive hearing

3.The new research________.

A. studied six Asian elephants

B. studied elephants in a zoo and in the wild

C. aimed to discover the elephants' disadvantages

D. proved that scientists' earlier beliefs were totally true