From the given options, select the Figure of Speech (Poetic Device) used in the expression:

She accepted it as the kind cruelty of the surgeon's knife.

Oxymoron

The correct answer is OPTION 1 -  Oxymoron.

An oxymoron is a figure of speech in which two contradictory terms are used together. In the expression "She accepted it as the kind cruelty of the surgeon's knife," the words "kind" and "cruelty" are contradictory. This creates a sense of paradox, which is appropriate because the speaker is describing the surgeon's knife as both helpful and harmful at the same time.

The other answer choices are incorrect. Pun is a play on words, simile is a comparison between two things using the words "like" or "as," and alliteration is the repetition of consonant sounds at the beginning of words. None of these devices are used in the expression "She accepted it as the kind cruelty of the surgeon's knife."