In the following question, out of the four alternatives, select the alternative which is the best substitute of the phrase.
One who considers the well-being of others
Altruist means a person unselfishly concerned for or devoted to the welfare of others.
Opponent means someone who competes with or opposes another in a contest , game or argument.
Antagonist means a person who actively opposes or is hostile to someone or something.
Protagonist means the leading character or one of the major characters in a play.
Hence, option 1 is the correct answer