Possible Clues:

• “Let me think... Huh-uh!”
• “...on second thought, pass”
• "Sorry, that's not happening"
• 'Sorry, that's not happening'
• "That sounds wrong"
• 'Yeah, that'll never happen'
• "Yeah, that'll never happen"
• “Dude, how could you think that?”
• 'Let me think ... hmm, I don't think so'
• "Uh ... uh-uh"