题目

Today is Sarah’s birthday. She is seventy-five. We asked a few old friends to dinner. Like most elderly people, I suppose, we spent most of the evening talking about old times. Thirty years ago, the village used to be a quiet place. Now it has changed. Every Sunday hundreds of cars pass through the village at what I think a dangerous speed. They make the village almost as noisy as the streets of a large town. As a boy I enjoyed riding on the backs of the farm horses. Things are different now. Today there are very few horses working on the farms. The farm workers today drive tractors,下图人物是南北朝时期著名的农学家，下列著作中由他编写的是 [     ]A．《农政全书》   B．《梦溪笔谈》     C．《齐民要术》 D．《天工开物》