Sentence Correction (SC) | Re: Seismologists studying the earthquake that struck northern

(A) the upward thrust that threw one man straight into the air, and the strange electromagnetic signals detected hours before the temblor=>correct
(B) the upward thrust that threw one man straight into the air, and strange electromagnetic signals were detected hours before the temblor=>incorrect 3rd investigation point
(C) the upward thrust threw one man straight into the air, and hours before the temblor strange electromagnetic signals were detected=> incorrect 3rd investigation point
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