Thomas Paine's pamphlet 'Common Sense' transformed the notion of independence from Britain into a viable idea for many colonists. It inspired a sense of urgency for change and helped shift public opinion towards supporting the revolution. Therefore, the correct choice is B. unthinkable idea.
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Thomas Paine's pamphlet "Common Sense" inspired the colonists by making the idea of independence from British rule feel achievable and necessary. It played a vital role in shifting public opinion and laid the groundwork for the Declaration of Independence. The concept of independence, previously deemed unthinkable by many, became a rallying call for revolution. ;