Are acts of altruism unique to human beings? From my experience I must say that they are also present in the animal world. I was raised on a farm and was brought up surrounded by animals. Once I was being attacked by a large dog and began yelling for help. A horse came running up from a distant field and chased away the dog. We also had a dog that protected our cat. When the cat was being attacked by other dogs, our dog drove them away by barking. Here, altruism means ( ).
1. acting bravely to protect one’s own honor
2. being true to oneself as well as to others
3. doing something for the sake of others
4. using your brain to understand a situation
ということは、選択肢 3. が正解ですね。