Sandy Missed Class Because She Is Sick, but Luis Did

Sandy missed class because she is sick, but Luis did attend the lecture. Sandy asks Luis if she can borrow his notes. If Luis considers Sandy's situation from her point of view and decides to offer help without expecting some form of payback, he is most likely

A) invoking the norm of reciprocal altruism.
B) operating under an altruistic motive.
C) operating under an egoistic motive.
D) following the negative state relief model.