Which probability indicates that an event will definitely occur?1412341

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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