Joey Works in the Mailroom of a Large Corporation

Joey works in the mailroom of a large corporation.One of his duties is to distribute the mail to the department heads in two different office buildings.One manager angered Joey by making a negative comment about the mail facility's management.Ever since,Joey makes sure to deliver this person's mail last,and is frequently a day late in delivering important documents to this particular manager.Joey's behavior is an example of .

A) hostile aggression
B) obstructionism
C) an expression of hostility