A farmer had a faithful horse who was old and couldn't do much work. So the farmer no longer wanted to give him anything to eat and said, " If you can bring me a lion here, I will keep you." The horse was sad, and went to the forest. There he met a fox. After the fox heard the story, he said. "I will help you. Just lie down, as if you were dead, and do not move.'' The horse did what the fox asked, and then the fox went to the lion and said, "A dead horse is lying out there. Just come with me, and you have a rich meal." The lion went with him, and they were both standing by the horse, the fox said, "Now let me tie the horse to your tail and you can take it home and eat it." The fox's words made the lion very happy. But the fox tied the lion's legs together with the horse's tail. When the fox finished his work, he said to the horse, "Pull the lion to the farmer." Then the horse pulled the lion away with him at once. The lion was very angry but he couldn't do anything. When the farmer saw the lion, he was in a good mood , and said to the horse, " You can stay with me.'' And he give him enough food to eat until the horse died. The farmer didn't want to keep his horse any more because _ . A) the horse was lazy B) the horse didn't follow the farmer's words C) the horse was ill D) the horse was too old to do much work.
Answer:
D