The correct answer is OPTION 1 - perplexed
The correct meaning of the idiom "at one's wit's end" is perplexed.
1. Perplexed: Feeling confused or puzzled; not knowing what to do next. This matches the meaning of "at one's wit's end."
2. Clear up: To make something easier to understand or to resolve a problem.
3. Explain: To make something clear or easy to understand by describing it in detail.
4. Enlighten: To provide someone with greater knowledge or understanding about a topic.
So, "at one's wit's end" means being perplexed.
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