While some historians explain the end of slavery in the americas throughout the nineteenth century as a response to the antislavery campaigns of liberal and christian abolitionists, a reading of the british decision to end the slave trade in 1807, and slavery in its empire in 1834, as equally utilitarian decisions, pragmatic attempts intended to stave off potential black revolution on the one hand, and to resolve?

Britain needed to resolve a conflict between the principles of free trade (which Britain was more and more adopting) and the institution of slavery.

Concerns about slave revolts indeed were indeed part of Britain's pragmatic decisions to end its participation in the slave trade in 1807 and phasing out slavery in its empire starting in 1834.  But the other factor was that the Industrial Revolution was taking over how the British economy operated, and the institution of slavery no longer fit within the new, industrializing economy.  

Along with those practical reasons, there was of course much moral pressure applied by the abolitionist movement.  William Wilberforce was a key voice of conscience in Parliament from the moral side of the argument.

The answer would be option a , b, and c.