• 'But of course!'
• 'Everyone knows that!'
• 'How obvious!'
• 'I already know that!'
• 'I'm such a dope!'
• 'Isn't that obvious?!'
• 'Silly me'
• 'That was stupid of me!'
• 'Well, how obvious!'
• 'Well, obviously!'
• 'Well, that's obvious!'
• Answer to a stupid question
• Any fool knows that!
• Any idiot knows that!
• Blank reply
• Bonehead's response
• Boy, am I a dope!
• Boy, am I dumb!
• Boy, am I stupid!
• Brow-slapper's syllable
• C'mon, too easy!
• Comment made while slapping the forehead
• Dolt's remark
• Doltish interjection
• Dopey comment
• Dumb reply
• Everybody knows that!
• Forehead slapper's comment
• Forehead slapper's exclamation
• Forehead-slapper's cry
• Forehead-slapper's syllable
• Head slapper's cry
• Head-slapping utterance
• Head-slapping word
• How could I be so dumb?
• How could I be so stupid?
• How could I have been so stupid?
• How could I miss that?!
• How dumb can I be!
• How dumb of me!
• How foolish of me!
• How forgetful of me!
• How silly of me!
• How stupid of me!
• How'd I miss that?
• I can't believe I blew that!
• I coulda thought of that!
• I knew that!
• I should have known that
• I should've known that!
• I should've seen that!
• I should've thought of that!
• I'm a moron!
• I'm not stupid, y'know
• I'm so dense!
• I'm so dumb!
• I'm so stupid!
• It's obvious
• It's so obvious!
• Like I didn't know that !
• Like stupid!
• Like, could it be more obvious?
• Like, dumb!
• Like, how did I make THAT mistake?
• Like, I get it
• Like, I knew that!
• Like, no kidding!
• Like, obviously!
• Lummox's remark
• Moron's comment
• No kidding, stupid!
• No kidding!
• No shit, Sherlock
• Now THAT'S a stupid question!
• Obviously!
• Of course I knew that!
• Of course, blockhead!
• Of course!
• Of course! in teenspeak
• Oh, I get it
• OK, I'm a dummy
• Okay, I get it already
• Response to the obvious
• Sarcastic acknowledgment
• Sarcastic response
• Sarcastic retort
• Self-deprecating utterance
• Simpleton's sound
• Simpleton's utterance
• Snerd word
• Sound of one hand slapping?
• Sound of stupidity
• Stupid response
• Tell me something I don't know!
• That much was obvious
• That was foolish of me!
• That was silly of me!
• That wasn't smart of me!
• That's not much of a revelation!
• That's obvious, stupid!
• That's obvious!
• That's obvious! in teen talk
• Too easy!
• Well, ___!
• Well, of course!
• Well, that was a no-brainer!
• Well, that's completely obvious!
• Well, yeah!
• What a dope I am!
• What a dope!
• What am I, stupid?
• What an idiot I am!
• What do you think I am, stupid?
• Who doesn't know that?
• Word accompanying a head slap
• Word from Snerd
• Word with a head slap
• Ya think?
• You didn't know that?
• You might say it when you get this answer