Which of the Following Is the BEST Example of Altruism

Which of the following is the BEST example of altruism?

A) Claire is a paid employee at a local nonprofit organization that helps homeless families.
B) John helps his brother with his chores,if his brother is willing to help him with his homework.
C) Roberto anonymously donates money every year to a local food bank.
D) Julie volunteers at a local hospital after school,because she thinks it will help her get into a good college.