阅读以下短文，根据短文内容，从题中所给A、B、C、D四个选项中，选择最佳答案
Einstein has to speak at an important science meeting. On the way there, he tells his driver that looks a bit like him, "I'm sick of all these meetings. I always say the same things over and over!"
The driver agrees, "You're right. As your driver, I attend all of them, and even though I don't know anything about science, I could give the speech in your place. "
"That's a great idea!" says Einstein. "Let's exchange our places then!"
So they exchange clothes. As soon as they arrive, the driver dressed as Einstein goes on stage and starts giving the usual speech, while the real Einstein, dressed as the car driver, attends it.
But in the crowd, there is one scientist who wants to show off and thinks of a very difficult question to ask Einstein, hoping he won't be able to answer. So this guy stands up and cuts in the speech by raising his very difficult question. The whole room goes silent, holding their breath, waiting for the answer.
The driver looks at him, dead in the eye, and says, "Sir, your question is so easy that I'm going to let my driver answer it for me."
