Possible Clues:

• 'Eureka!'
• 'Aha!'
• "Aha!"
• This person has a certain appeal, making a claim to know the answer
• Eureka! The setter's got sex appeal!
• 'Here's the solution!'
• ''Eureka!''
• "Oh, of course!"
• It might be said by one who has found the answer
• Puzzle solver's exclamation