Select the correct answer.
In 1946, Peter Goldmark created a mechanical device for a color television system. How did the device work?
A.
A red-blue-green thread was waved in front of a series of discs.
B.
A red-blue-green tube was swung in front of a beam of light.
C.
A red-blue-green wheel was rotated in front of a cathode ray tube.
D.
A red-blue-green box was placed in front of a row of lamps.