Related Clues:

• Forehead-slapper's cry
• "That's clear to me"
• "Of course!"
• 'Indeed'
• 'Boy, am I dumb!'
• "How could I be so stupid?"
• "How obvious!"
• 'Isn't that obvious?'
• 'Isn't that obvious?'
• 'Well, that's obvious!'
• Bonehead's response
• 'Well, ___!'
• 'How obvious!'
• ''Obviously!''
• ''Well, that's obvious!''