The correct option is A Thomas Clarkson
The Society for Effecting the Abolition of the Slave Trade (or The Society for the Abolition of the Slave Trade) was a British abolitionist group, formed on 22 May 1787, by twelve men who gathered together at a printing shop in London. The Society worked to educate the public about the abuses of the slave trade; it achieved the abolition of the international slave trade in 1807, enforced by the Royal Navy. Three Anglicans were founding members: Thomas Clarkson, campaigner, and author of an influential essay against the slave trade; Granville Sharp who, as a lawyer, had long been involved in the support and prosecution of cases on behalf of enslaved Africans; and Philip Sansom. Hence, Option A is correct. Among the rest, Thomas Paine was an England-born political philosopher and writer who supported revolutionary causes in America and Europe. Published in 1776 to international acclaim, Common Sense was the first pamphlet to advocate American independence. William Pitt the Younger was a prominent British Tory statesman of the late-eighteenth and early-nineteenth centuries. He became the youngest Prime Minister of Great Britain in 1783 at the age of 24 and the first Prime Minister of the United Kingdom as of January 1801. None of the other options advocated the abolition of slavery, hence, incorrect.