Final answer:
The most appropriate phrasal verb to complete the sentence 'They performed the story on stage' is 'acted out'.
Step-by-step explanation:
The most appropriate phrasal verb to complete the sentence 'They performed the story on stage' is acted out. This phrasal verb means to represent a story or situation using gestures, movements, and expressions. 'Acted on' and 'acted upon' are incorrect phrasal verbs. 'Acted in' could also be a possible option, referring to performing a story as an actor on stage.
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