Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

[EX Q]: On January 26, 1879, who was granted a patent for r an electric lamp using a carbon filament or strip coiled and connected to platina contact wires?
[EX A]: incandescent light bulb

[EX Q]: Which American actor and singer has joined Amanda Holden as one of the judges on the current series of 'Britain's Got Talent'?
[EX A]: britain's got talent

[EX Q]: A Dobro is what type of musical instrument?
[EX A]:
dobro