Explanation:

- The group of words describes "Unselfish interest in the welfare of others," which means a genuine concern for the well-being of others without expecting anything in return.

- Option 1: Egoism

- This refers to a self-centered approach where a person prioritizes their own interests over others. It is not related to being unselfish.

- Option 2: Celibacy

- It means abstaining from marriage or sexual relations, which is unrelated to the concept of caring for others' welfare.

- Option 3: Misanthropy

- This is a dislike or distrust for humankind, the opposite of showing interest in others' welfare.

- Option 4: Altruism

- Altruism is the correct term describing selfless concern and actions for the well-being of others.