Once James Thornhill, a famous English painter, was asked to paint some pictures on the walls of the king's palace in England. Then workers were sent for and a big platform（台子）was made. With the help of a worker, Thornhill started painting on the platform. They worked for a whole year and at last the pictures were ready. Thornhill was happy when he looked at the pictures, for they were really beautiful. He looked at them for a long time, and then took one step back and looked again. Now the pictures were even more beautiful. He took another step, then another. Finally he was at the very edge of the platform, but he didn't know it because he was thinking of his pictures. The worker saw everything. "What should I do?" he thought. "Thornhill was at the very edge of the platform. If I cry out, he will take another step, fall off it and surely be killed. "So the worker quickly took some paint（漆）and threw it at the pictures. "What are you doing?" cried the painter, running quickly forward to his pictures.
He was ordered to ______. A paint the wall of the king's palace in England B paint some pictures on the wall of the palace C build a big platform in front of the palace D put up some new pictures on the old wall