Final answer:
President Obama's 2008 campaign used social media effectively during the coalescence stage of social movements to engage and organize supporters by raising awareness and creating a digital grassroots movement.
So, the correct answer is B) Coalescence stage.
Step-by-step explanation:
President Obama's 2008 presidential campaign effectively utilized social media during the coalescence stage of social movements. The campaign harnessed platforms to unite and organize people, especially those not previously engaged in politics, to publicize the political issues and support the campaign.
This stage involves the joining together of individuals to organize and raise awareness about the social movement they represent, which the Obama campaign demonstrated by creating a powerful digital grassroots movement that transcended geographical boundaries and revolutionized political campaigning.
So, the correct answer is B) Coalescence stage.