Answer:
D. Something or someone that is not capable of making a mistake.
Step-by-step explanation:
The word infallible comes from Medieval Latin infallibilis. It is a derivated of fallible which means: capable of mistakes. Which also has a birth word that is fail.
By adding the prefix in- that means not, opposite of, the capacity of mistaking is canceled and therefore someone or something infallible is exempt from error in judgment, knowledge or opinion.
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