The oldest stone buildings in the world are the pyramids(金字塔). They have stood for nearly 5, 000 years, and it seems likely that they will continue to stand for thousands of years yet. There are over eighty of them scattered(散布)along the banks of the Nile, some of which are different in shape from the true pyramids. The most famous of these are the “Step” pyramid and the “Bent” pyramid.

　　Some of the pyramids still look as much alike as they must have been when they were built thousands of years ago. Most of the damage suffered by the others has been at the hands of men who were looking for treasure or, more often, for stones to use in modern buildings. The dry climate of Egypt has helped to keep the pyramids in good condition, and their very shape has made them less likely to fall into ruin. These are good reasons why they can still be seen today, but perhaps the most important is that they were planned to last forever.
　　The “Step” pyramid had to be on the west side of the Nile, the side on which the sun sets. This was for spiritual reasons. It also had to stand well above the level of the river to protect it against the regular floods. It could not be too far from the Nile, however, as the stones to build it needed to be carried in boats down the river to the nearest point. Water transport was, of course, much easier than land transport. The builders also had to find a rock base, which was not likely to crack(破裂)under the great weight of the pyramid. Finally, it had to be near the capital, or better still near the king’s palace so that he could visit it easily to personally check the progress being made on the final resting place for his body.
According to the passage, the “Step” pyramid　　　　.

A．is unlikely to fall into ruin in the near future

B．was built on the sand along the Nile

C．is one that was built later than the true pyramids

D．is the most famous of the true pyramids

The most important reason why some pyramids remain in good condition is that　　　　.

A．people have taken good care of them

B．it doesn’t rain often in Egypt

C．they were well designed

D．the government has protected them from damage

Most of the damage to the pyramids has been caused by　　　.

A．the regular floods

B．the dry climate of Egypt

C．people searching for gold

D．people in search of building materials

The Egyptians built the pyramids along the banks of the Nile because　　　　.

A．they believed in their god

B．it was difficult to find a large rock base far from the Nile

C．the river helped a lot in the transport of building materials

D．it was not easy to choose a suitable place for the pyramids