题目内容：

    Very few animals except dolphins, chimpanzees (黑猩猩)，and elephants have ever passed the mirror test for self-recognition. Scientists believe they have found a fish able recognize itself in a mirror. The result is surprising because this ability is usually only found in animals with bigger brains. Even humans don't usually pass the mirror test until they are about a year and a half old.

To test the wrasse (隆头鱼), a small fish in the sea, scientists put each wrasse in a tank with a mirror. They gave the fish a chance to get used to the mirror and watched their reactions. At first, the wrasses challenged the "other fish" by swimming up to the mirror and "fighting" them with the mouth. But soon the wrasses seemed to understand that something funny was happening. They began to swim toward the mirror upside down or in other unusual ways. It was like they were testing whether the fish in the mirror were really themselves.

Once the wrasses seemed used to the mirror, the scientists gave the wrasses a mark by putting the fish to sleep and injecting something under their skin. Some of the fish got a brown mark. Other fish got a clear "mark" that didn't have a color and couldn't be seen in a mirror.

After looking in the mirror, the wrasses with the brown marks would rub the area with the mark against the sand in the bottom of the tank. Then they would go back and look in the mirror again, as if checking if the mark was still there. But when wrasses with brown marks were put in tanks without mirrors, they didn't try to rub their marks away. And wrasses with clear "marks" didn't either, even when they could see themselves in the mirror.

The unexpected results are making some people look hard for other ways to explain how the wrasses reacted. So even though the wrasses seem to have passed the mirror test, the scientists will need some time to reflect on exactly what that means.

1.Why do the scientists feel surprised about the result?

A.The fish has a big brain.

B.Elephants failed to pass the mirror test.

C.Chimpanzees are as clever as dolphins.

D.The fish succeeded in passing the mirror test.

2.What did the scientists take notice of about the wrasses at first?

A.They swam in unusual ways.

B.They were unaware of themselves in the mirror.

C.They thought the mirror interesting.

D.They wanted to challenge themselves.

3.How did the fish with brown marks react in the mirror test?

A.They would rub the area with the mark against sand.

B.They would pay no attention to marks.

C.They would rest in the bottom of the tank.

D.They would swim upside down to the mirror.

4.Which can be a suitable title for the text?

A.Why Are Fish Smarter than Expected?

B.Do Colors Affect the Experiment?

C.How Is the Mirror Test Conducted?

D.Can Fish Recognize Themselves in the Mirror?