Stalin is using B. Pathos.
Ethos, Pathos, Logos and Telos are modes of persuasion used to convince the audiences. In this case Stalin is using the pathos mode because he appeals to the emotion of the audience, to inspire anger from them. The speaker who employs this audience appeal wants to make the audience feel a certain emotion, in this anger and fear, by the use of certain type of adjectives to emphasyze his idea.
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