Carlos is asked by his teacher to closely observe the pixels on a television screen with a magnifying glass. He is told that each pixel emits one color of light at a time and that the colors emitted by adjacent pixels combine to create an image on the television screen. His teacher asks him to identify which colors the pixels emit. Carlos knows that any shade of paint can be made out of red, blue, and yellow paint. So he decides not to closely observe television and concludes that television pixels must emit red, blue, or yellow light to generate an image. How did Carlos reach his conclusion?
A. He closely observed the colors of television pixels emitted.
B. He conducted a controlled experiment.
C. He proved that the properties of light are the same as those of paint.
D. He let his prior expectations bias his investigation.