Which source has the best credibility for a research paper about the battle of gettysburg?

Which would be the most credible source for researching the effects of smoking? letter from your grandfather web page about someone’s lung cancer report prepared by a tobacco company research article in a scientific journal

What causes cassius to delay killing caesar? a. the crowds around caesar b. a violent storm c. brutus’s reluctance d. the disorganization it the resistance

His is a verbal or oral response to an argument presenting an opposite viewpoint. slanted wordstabloid thinkingappeal to authoritybandwagoncard stacking generalityintertextual referencesname callingplain folks tactics