Choose the word whose underlined part is pronounced differently from the others

I - Choose the word whose underlined part is pronounced differently from the others.
1. A. claimed B. warned C. occurred D. existed
2. A. health B. appear C. ready D. heavy
3. A. tidal B. sight C. mineral D. describe
4. A. though B. throw C. through D. thought
5. A. thunder B. erupt C. trust D. pull
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