Sheila and Jacob don't like each other very much. From the very beginning, Jacob has resented Sheila for stealing his best friend away from him. At the same time, while Sheila didn't have a problem Jacob initially, she now ignores him every time they all hang out together. Neither party has done anything overtly offensive toward one another. If that's the case, then which of the following best explains how the animosity between Sheila and Jacob began?
a. Jacob and Sheila have distinctly different personalities and probably didn't get along from the beginning.

b. Sheila sensed Jacob's resentment and started behaving negatively toward him.

c. Jacob's resentment manifested itself in negative behavior toward Sheila. This triggered Sheila to behave negatively toward Jacob.

d. Sheila's dislike of Jacob caused her to behave negatively toward him. This caused Jacob to develop negative feelings toward her.

e. Both Jacob and Sheila have resentment toward each other. They behaved in negative ways toward each other, which caused them to dislike each other