Answer:
D. alliteration
Step-by-step explanation:
Oxymoron: figurative language where two contradictive terms appear together (i.e. all alone). There's no oxymoron here, though.
Onomatopoeia: figurative language with a word that represents a sound. There's no onomatopoeia here, though.
Allusion: a form of figurative language where one mentions something indirectly. (i.e. he's a Romeo with the girls). There's no allusion here, though.
Alliteration: figurative language where many words begin with the same sound. There is alliteration here: sudden stillness, everyone snoring.
Therefore, the answer is D.
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