Which mystery novel by Sir Arthur Conan Doyle features the detective Sherlock Holmes solving the mystery of a stolen blue gem known as the Blue Carbuncle?
A. The Blue Carbuncle
B. The Adventure of the Speckled Band
C. The Sign of Four
D. The Musgrave Ritual
"The Adventure of the Blue Carbuncle" by Sir Arthur Conan Doyle features Sherlock Holmes solving the mystery of a stolen blue gem known as the Blue Carbuncle.