Final answer:
Dante and his guide Virgil return to Earth by climbing down Satan's fur in Dante's Inferno; none of the provided options are correct.
Step-by-step explanation:
In Dante's Inferno, after the exhaustive journey through the circles of Hell, the narrator and his guide, Virgil, reach the Earth's surface. The correct answer to the question is not among the provided options. Instead, Dante and Virgil exit Hell by climbing down Satan's fur and then emerge in the Southern Hemisphere, where they see the stars in the sky indicating they are back on Earth's surface. They do not fly on the back of a giant eagle, climb a staircase made of bones, are transported in a boat, or use a magical teleportation device. The journey back to Earth signifies a transition from sin to repentance and contemplation of the stars indicates hope for divine grace.