The correct option is B An attempt to blow up the Houses of Parliament
Gunpowder plot was the conspiracy of English Roman Catholics to blow up Parliament and King James I, his queen and his eldest son on November 5, 1605. The leader of the plot, Robert Kastesby, together with his four co conspirators- Thomas Winter, Thomas Percy, John Wright, and Guy Fawkes were zealous Roman Catholics angered by James's refusal to grant more religious toleration to Catholics.