According to self - esteem maintenance theory (e.g , Tesser, 1991), people will be more inclined to help a stranger than to help a friend when
a. their help might enable our friend to surpass us on an important dimension.
b. their friend has refused to help us in the past.
c. they are the only people witness to the other person's need.
d. the costs of helping are relatively low, and the rewards are high.