阅读理解。
Recently, many of America's biggest zoos have decided to close down their elephant exhibits.
A new study shows that elephants live better in the wild.
Researchers studies 4,500 elephants in European zoos and compared them with elephants living
in wild. They found that wild elephants are healthier, live longer and reproduce(繁殖) more than those
kept in zoos.
Many animals live longer in zoos than those who live in the wild. In zoos, they are not worried
about some animals that may attack them at any time when in the wild. There's always plenty to eat.
And they are cured when sickness strikes. But when it comes to elephants, the situation is different.
The researchers said that zoos do not offer enough space for elephants to walk about as much as
30 miles a day. Too little exercise and too much food are causing zoo elephants to put on extra pounds.
The weight gain can lead to heart disease and other health problems. Even the baby elephants born in
zoos are heavier than those born in the wild.
Bringing Asian and African elephants together in zoos has also caused problems. A disease that is
not dangerous for African elephants has spread to Asian elephants, and is harming them. " Zoos have
accidentally created this," says Mason. "It's killing Asian adult elephants."
Exerts point out that keeping elephants in zoos isn't a problem for the animals only; it's also quite
costly for humans. In the last 10 years, zoos have spent about $500 million on caged space for about
250 animals.
1. Compared with wild elephants, elephants in zoos ______.
A. live longer
B. are heavier
C. are healthier
D. reproduce more
2. The fourth paragraph mainly tells us that ______.
A. baby elephants are difficult to live in zoos
B. elephants walk as long as miles a day
C. little room to wander leads to problems for elephants
D. too much food in zoos leads to heart disease for elephants
3. What can we learn from the passage?
A. Asian elephants are more easily attacked by diseases than African elephants.
B. The diseases of zoo elephants are caused by being overweight.
C. Zoos free the elephants because of the cost of keeping them.
D. Elephants live better in the wild than in zoos.
4. The passage is probably taken from _____.
A. the zoo rules
B. a guide book
C. a healthy program
D. a science magazine