Minde Goes to a Coffee Shop During His Study Break

Minde goes to a coffee shop during his study break. When he gets to the front of the line, the cashier tells him there is no charge because the previous customer actually went ahead and paid for both of their coffees. Minde is pleasantly surprised by the goodwill of this stranger. According to research on the reciprocity norm, Minde will now:

A) experience diffusion of responsibility for helping strangers.
B) be less likely to help a relative over a stranger.
C) acquire an increased sense of duty to help others.
D) be more likely to help someone else in the near future.