possibility vs sure bet

possibility

noun
  • The quality of being possible. 

  • An option or choice, usually used in context with future events. 

  • A thing possible; that which may take place or come into being. 

sure bet

noun
  • Synonym of safe bet, good bet, fair bet 

How often have the words possibility and sure bet occurred in a corpus of books? (source: Google Ngram Viewer )