Correct Answer:
D. From
This question tests your knowledge of prepositions used with specific verbs. The verb "refrain" is always followed by the preposition "from" when it means to stop oneself from doing something or to deliberately avoid an action.
In the sentence "He has refrained from doing this," the phrase "refrain from" is a fixed expression in English. The other prepositions—with, of, and by—do not correctly collocate with the verb "refrain" in this context.
- Correct Phrase: Refrain from doing something.
- Meaning: To avoid or stop oneself from performing an action.
- Grammar Rule: The verb "refrain" is always followed by the preposition "from".
Therefore, the correct answer is: "From".
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