[单选,材料题] What can we conclude from this passage?

回答下面的题目
Two hundred years ago, American students went to American schools．  Like you, they studied arithmetic, spelling and geography． Unlike you, they also studied Greek and Latin． In fact, students spent more than half their time studying Greek and Latin．
The same was true for most students in Europe． Until the seventh century, all educated Europeans knew Latin．  It did not matter if they lived in England or Italy or France or Spain．  If they were educated, they knew Latin．
During the seventh century, educated Europeans began to study Greek as well as Latin． Greek and Latin had been the leading languages of the ancient Greeks and Romans． All educated Europeans were expected to know these languages．
To educated Europeans, the languages of the Greeks and the Romans were important． The ideas of the Greeks and Romans were also important． People knew that many of their own ideas had come from the Greeks and the Romans． To understand their own culture, they must understand its origin． They knew that those beginnings lay in the classical world．
Today we have so many things to study that few people have time to learn Greek and Latin． Few of you will study either language in school． Yet the ideas of the Greeks and the Romans are still important to us． These ideas still help to shape Western culture today． To understand our own culture, we must understand the culture of the classical world．

A good synonym for "origin" is________