Related Clues:

• [Forehead slap]
• 'Thank you, Captain Obvious!'
• ''C'mon, that's too easy!''
• Part 1 of a wordplay-related quip
• ''Silly me!''
• "Well, of course!"
• 'Uh, yeah!'
• 'That's obvious!'
• 'This ___' (1979 hit)
• "This ___" (1979 hit)
• 'I *finally* got it!'
• Response to an obvious statement
• Words starting many a guess
• 'Oh yeah?'
• 'What a dope I am!'