Possible Clues:

• 'Ob-vi-ous-ly!'
• 'Oh, yeah, really?'
• ''Well, isn't it obvious?!?''
• "As if I didn't know that!"
• 'Obviously, Einstein!'
• 'It's as plain as day!'
• 'Well, that's obvious'
• 'Ya think?'
• “Well, obviously!”
• "That was obvious"