I once experienced an unforgettable trip to Gloucester to see some of the world's most beautiful and exciting animals in their own habitat(栖息地), the North Atlantic Ocean.
After a long trip by bus, we got on the ship. After a while, we stopped and everyone on the ship started to shout because we saw a humpback whale(座头鲸). It was wonderful. Sometimes, whales came so close to the ship that you thought you could easily touch them.
While we were watching the whales, a guide was giving us some information about them. She told us that we saw only two kinds of whales -- 50-foot humpback whales (singing whales) and 70-foot fin back whales (the second largest whales on earth). She also said we could easily recognize a whale by its tail because every whale has a different kind of tail just like people have different fingerprints.
They all have names, and on this trip, we saw "Salt" and "Pepper", two whales named by a biologist and a fisherman. They were swimming together all the time.
I took twenty-seven photos, but it was very hard to take them because the whales were quick and stayed on the surface(表面) of the ocean just for a short time. It was really something. It was one of the chances that a person hardly ever experiences in life, but I had that chance.
This passage is mainly about ____.

A．an unforgettable experience in the forest

B．an unforgettable trip to see some strange animals in the mountains

C．a long trip on the ship

D．an unforgettable trip to watch whales

Everyone on the ship began to shout because ______.

A．a whale came so close to the ship	B．they saw a singing whale
C．they saw a fin back whale	D．they could touch the whale

When they were watching the whales, ____.

A．some of them fed the whales

B．they found several kinds of whales

C．a guide told them something about the whales

D．some of them took many photos and touched the whales

How can we recognize a whale?

A．By its tail(认识).	B．By its head.
C．By its neck.	D．By its eyes.