This literary character and his friend go looking for a missing student in The Adventures of the Priory School which is in a collection entitled The Return of this character. This character had seemingly died in the story, The Final Problem, when he fell to his death from Reichenbach Falls while struggling with arch-enemy James Moriarty, only to reappear in the author's prequel, The Hound of the Baskervilles. For 10 points, name this literary detective who lives at 221B Baker Street in London, whose friend and partner is Dr. Watson, and who was created by Sir Arthur Conan Doyle.
a) Hercule Poirot
b) Sam Spade
c) Sherlock Holmes
d) Philip Marlowe