Prefix refers to the word or letter that is added before a word. The meaning of the prefix im- in the word immaterial is the opposite of.
What is Prefix?
The prefix is defined as the letters or group of letters, added at the beginning of a word that changes the meaning of the word.
The prefix im- in the word immaterial changes the meaning of the word from significant to not significant.
Therefore the meaning of the prefix is the opposite of.
Hence the correct option is A.
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