Which event contributes most to the "reward" at the end of the story?

Which of these is a consistent periodic pulse separated into equivalent intervals of time?

Acurious child asked his mother: “mommy, why are some of your hairs turning grey? ” the mother tried to use this occasion to teach her child: “it is because of you, dear. every bad action of yours will turn one of my hairs grey! ” the child replied innocently: “now i know why grandmother has only grey hairs on her head.”

What are some signs of a food allergy reaction?