"Where is Papa going with that ax  ?" said Fern to her mother as they were setting the table for breakfast. "Out to the hoghouse," replied Mrs. Arable. "Some pigs were born last night." "I don't see why he needs an ax," continued Fern, who was only eight. "Well," said her mother, "one of the pigs is a runt  . It's very small and weak. So your father has decided to do away with it." "Do away with it?" shouted Fern. "You mean kill it?" "Don't shout, Fern!" she said. "Your father is right. The pig would probably die anyway." Fern pushed a chair out of the way and ran outdoors. The grass was wet and the earth smelled springtime. Fern's shoes were wetting by the time she caught up with her father. "Please don't kill it! It's unfair," she said. Mr. Arable stopped. "Fern," he said gently, "you will have to learn to control yourself." "This is a matter of life and death, and you talk about controlling myself." Tears ran down her cheeks and she took hold of the ax and tried to pull it out of her father's hand. "Fern," said Mr. Arable, "I know more about raising a group of pigs than you do. A weak pig makes trouble." "But it's unfair," cried Fern. "The pig couldn't help being born small. If I had been very small at birth, would you have killed me?" Mr. Arable smiled. "Certainly not," he said, looking down at his daughter with love. "But this is different. It's a pig." "There is no difference," replied Fern. According to the passage, Fern's father thought that   _  .
it was natural for pigs to be born small he couldn't afford to have so many pigs a weak pig needed more attention he was troubled by raising a weak pig