The correct answer is: [D]: " 1 " .
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A probablility of "1" means that an event "DEFINITELY WILL OCCUR" (by definition).
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Note:
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One cannot have a "probability" of a [value greater than "1"] ;
→ As such, answer choices:
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[A]: "14" ; [B]: "12" ; [C]: "34" ; all are incorrect.
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