Final answer:
The bolded words in the song lyrics are an example of onomatopoeia.
Step-by-step explanation:
The bolded words in the song lyrics are an example of onomatopoeia. Onomatopoeia is a literary device in which words mimic the sounds associated with the objects or actions they refer to. In this case, the words 'boom' and 'oh' are used to represent the sound of fireworks exploding and the admiration of the audience, respectively.
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