阅读理解 阅读下列材料，根据其内容选择最佳答案。          �

Compass

It was a great gift to the world from ancient China. Before it was invented, sailors had to depend on the stars to find direction. After it was invented, the oceans were open to travel. And many new discoveries were made with the help of it.

Gunpower

It was one of the greatest inventions. It is said that in the 3rd century a Chinese man wrote about how to make it. At lirst, it was used for making fireworks. At the end of the Tang Dynasty, people began to use it in wars. The method of making it was brought to the Arab world and Europe in the 13th and 14th centuries.

Paper-making

China was the first country in the world to make paper. During the Western Han Dynasty (202B.C.~9A.D.), paper was made in some places in China. It was developed in the Eastern Han Dynasty (25A.D.~ 220A.D.) by Cai Lun. He made paper with bark, ropes, rags and so on. Before it was invented, the ancient Chinese carved characters on animal bones and stones. They also wrote them on bamboo and wooden sticks.

Printing

It was developed in 1041-1048 in the Song Dynasty. A man named Bi Sheng carved characters on pieces of clay and wood. Then he put ink on them. After the characters were printed on paper, the pieces of clay or wood could be used again.This technology then spread to Korea, Japan and Europe. It was the basic method atthat time.