In "Public Relations Research," authors Don. W. Stacks and Marcia Watson DiStaso define PR research as "the preparation of gathering of __________ in support of a campaign to inform or change a public's perception of behavior." Which of the following words should be added in the blank to complete the sentence?
a) Information
b) None of the words listed here
c) Public opinion polls
d) Theories
e) Data
f) Academic journals