Answer: a. Lucifer's teeth are flat.
As Dante and Virgil arrive to the Ninth Circle of Hell, they spot Lucifer, also known as Satan. He is described as a giant who is trapped in ice up to his chest. He has two enormous wings and three faces. Each of these faces chews the body of a sinner. William Blake's depiction incorporated all of these elements, except for the addition of flat teeth on Lucifer's faces.