Difficulty: Easy
Correct Answer: Irrelevant
Explanation:
Given data
Concept/Approach
The straight antonym is 'Irrelevant' = not connected with the subject.
Why other options fail
Irrational: lacking reason; not the opposite of 'relevant'.Irregular: uneven/not routine; different semantic axis.Insistent: persistent; unrelated to relevance.
Final Answer
Irrelevant
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